Material Tests for Welding 201

alloy

A material consisting of a mixture of two or more elements, one of which must be metal. Alloys combine the beneficial properties of the mixed elements.

alternating current

AC. An electrical current that reverses direction at regularly recurring intervals of time. In the United States, alternating current reverses 120 times per second, or 60 hertz.

aluminum

A lightweight, highly conductive, silvery metal. Aluminum has good weldability, but certain factors, such as its melting point, can make the process difficult.

American Petroleum Institute

API. A non-profit organization that regulates industrial standards for the oil and natural gas industry in the United States. American Petroleum Institute codes are used for welding operations on oil pipelines and related materials.

American Society of Mechanical Engineers

ASME. An organization that publishes technical materials and sets industrial and manufacturing standards in the United States. The American Society of Mechanical Engineers' welding codes are used for projects involving high-pressure piping.

American Welding Society

AWS. A professional organization that supports the welding industry and promotes welding and related processes in the United States. The American Welding Society provides industry-standard codes and certification procedures.

amperage

The amount of current flowing in a circuit. Amperage is measured in amperes (A), or amps.

anvils

Fixtures used to hold specimens in place during impact testing. Anvils may be designed differently depending on the testing type and the orientation of the test specimen.

austenitic

A stainless steel that contains the greatest amounts of chromium, nickel, and other alloying elements. Austenitic stainless steels are the most corrosion-resistant stainless steels.

automated

A system or process that operates with limited human intervention. Automated systems include CNC machines and robotic equipment.

AWS

American Welding Society. A professional organization that supports the welding industry and promotes welding and related processes in the United States. The AWS provides industry-standard codes and certification procedures.

band saw

A saw that uses a flexible blade constructed from a continuous loop or band of metal. Band saws can be used to produce rough cuts and separate metal for additional processing.

base metal

One of the metals that are welded together to form a joint. The base metal and its properties influence the type of welding and the type of electrode that should be used.

bend jig

A fixture that provides a stable platform for part. Bend jigs are designed to meet inspection standards to ensure a consistent and controlled bend and reliable results during weld bend testing.

brale

A conical diamond indenter used in Rockwell hardness testing. The brale's depth of penetration determines the metal's hardness.

bridge cam gage

A weld gage designed to inspect the leg length and throat size of fillet welds, the reinforcement of groove welds, and other features. A bridge cam gage can also inspect undercut, porosity, misalignment, and angle of preparation.

butt joints

A joint created between two parts that lie in the same plane. Butt joints are simple, common joints.

calibrate

To compare and adjust a device or machine with unknown accuracy to a device with a known, accurate standard. Technicians calibrate some nondestructive testing equipment to specific standards in order to eliminate any variation.

calipers

Measuring instruments that include one or more sets of jaws and a scale marked with unit divisions. Calipers often include one set of jaws to measure outside diameters and another set of jaws to measure inside diameters.

capillary action

The absorption or propulsion of liquid caused by surface tension. Capillary action causes the penetrant to absorb into the surface of a part and any flaws in penetrant testing.

carbon

A common nonmetallic element found in ferrous metals like steel and cast iron. Increasing the carbon content of a metal typically increases its hardness.

carbon steels

The most basic form of steel, containing less than 3.0% alloying elements. Carbon steels are divided into low-, mild, medium-, and high-carbon steels.

certified welding inspector

CWI. A person certified by the American Welding Society to perform visual inspections on welds. Certified Welding Inspectors must be able to identify possible welding discontinuities and defects, use measuring instruments, and monitor any repairs.

Charpy V-notch testing

An impact testing method that uses a pendulum hammer to strike and break the unnotched side of a horizontal test piece secured on either end. Charpy V-notch testing allows inspectors to not only measure the strength of a weld but also examine it for internal defects.

chemical analysis

Testing that determines the elemental composition of materials and the concentrations of the elements. Chemical analysis of base metals, filler metals, and welds may be necessary to ensure weld quality.

circumference

The boundary or perimeter around a circle. Circumference measures the distance around a circle.

coil

A series of multiple loops of conducting wire used to create a magnetic field when current passes through it. Coils are used to create the currents necessary for electromagnetic testing.

compressive strength

The ability of a material to resist forces that attempt to squeeze or crush it. Compressive strength is described as the amount of compressive stress a material can withstand before fracturing.

constant amplitude testing

A fatigue testing method that applies an identical load throughout the testing process. Constant amplitude testing is used to identify a weld's fatigue strength.

convex

Curving outward like the exterior surface of a circle or sphere. The convex weld surface is inspected during bend testing.

copper

A reddish metal that is very ductile, thermally and electrically conductive, and corrosion resistant. Copper is often used to make electrical components.

corrosion resistance

The ability of a material to resist deterioration and chemical breakdown due to surface exposure to certain conditions. Corrosion resistance is an important physical property of finished welds.

couplant

A substance, usually an oil, used in ultrasonic testing to eliminate air gaps between the surface of the transducer and material. Couplants are needed to help movement and transmit sound waves during an ultrasonic test.

cross-section

The shape and surface of a weld and HAZ at the front of the weld. The cross section of a weld can be exposed by cutting or breaking a weld, which is done in various testing methods.

defects

An irregularity in the specified and expected composition of a weld that exceeds the part design's specifications or standards. A defect is an unacceptable discontinuity.

destructive testing

DT. A testing method that damages or destroys the workpiece being tested. Destructive testing is ideal for determining the strength of weld metal and base metal.

developer

A substance that helps to bring penetrant to the surface of a part in penetrant testing. Developer helps identify the presence of surface flaws.

digital analysis software

A computer program that simplifies and automates the collection and organization of data. Digital analysis software can help technicians interpret the results of ultrasonic testing.

direct magnetization

Establishing a magnetic field in a part by passing current through it. The prod method of magnetic particle testing uses direct magnetization.

discontinuities

An irregularity in the specified and expected composition of a weld. A discontinuity is not a defect if it still meets inspection criteria.

ductility

The ability of a material to be drawn, stretched, or deformed without breaking. Higher ductility is more common in softer metals.

duplex

A stainless steel that typically consists of a microstructure of 50% ferrite and 50% austenite. Duplex stainless steels have higher strength than austenitic steels and better corrosion resistance than ferritic steels.

dwell time

The amount of time a penetrant is permitted to remain on a test surface to allow it to be drawn into discontinuities. Dwell time depends on a number of different variables, including the type of metal being tested.

echo

Reflected ultrasonic waves that return from the material to the probe. Echoes are used to analyze materials and detect flaws.

eddy current testing

ECT. A nondestructive testing method that uses electromagnetic induction to detect surface and near-surface discontinuities and defects. Eddy current testing, or electromagnetic testing, is limited to use on electrically conductive materials.

electrical conductivity

The ability of a material to act as a medium for conveying electricity. Electrical conductivity is high for most metals.

electrode

A component in an electrical circuit that conducts electricity. A welding electrode generates the welding arc and can also act as filler metal.

electrode certification

The process of ensuring that electrodes meet the AWS specifications required for a project. Electrode certification typically requires testing that measures tensile strength.

electromagnet

A magnet that exerts attractive and repulsive forces only when energized by electric current. An electromagnet is typically formed by wrapping wire around an iron core.

electromagnetic testing

ET. A nondestructive testing method that uses electromagnetic induction to detect surface and near-surface discontinuities and defects. Electromagnetic testing, or eddy current testing, is limited to use on electrically conductive materials.

etch testing

A destructive testing method that involves applying a mildly acidic mixture to a cross-section of a welded joint and examining it for visible flaws. Etch testing includes macro- and micro-etch testing.

exposure angles

The angle at which X-rays or gamma rays are directed towards an object during radiographic testing. Exposure angles are used to ensure that the image is captured correctly.

fabrication

The process of creating or building parts from raw materials. Fabrication methods include forming, molding, and joining processes like welding and assembly.

fatigue

The weakening of metal caused by repeatedly applied force. Fatigue occurs in all metals, even very strong and hard ones, over time.

fatigue strength

The maximum stress a part can withstand for a specific number of repeated applications or loads prior to its failure. Fatigue strength is measured in fatigue testing by simulating the real-world loads experienced by welded components.

fatigue testing

A destructive testing method that repeatedly applies a stress amplitude load to a weld to determine its fatigue strength. Fatigue testing helps predict the lifespan of a weld under operational stress.

fatigue testing machines

A type of testing equipment designed to apply realistic loads to materials and parts to evaluate their fatigue strength. Fatigue testing machines often include hydraulic presses and hexapods.

ferritic

A stainless steel that contains high amounts of chromium and can include small amounts of molybdenum, aluminum, and titanium. Ferritic stainless steels have high hardness but low ductility.

ferrous metals

A metal that primarily contains iron. Ferrous metals are the most common type of welded materials.

file

A steel tool with a rough surface used to wear away material. Files are used in file scratch testing to evaluate hardness.

file scratch testing

A hardness test that involves attempting to remove material with a steel file. File scratch testing can be used to determine the relative hardness of materials.

filler metals

Any metal deposited into the weld that often adds strength and mass to the welded joint. In some welding processes, the electrode acts as the filler metal.

fillet weld break testing

A destructive testing method that involves breaking one side of a fillet weld sample. Fillet weld break testing can provide useful weld quality information to the inspector, such as strength and the presence of defects.

fillet weld gage blade

A weld gage designed to determine whether or not a fillet weld is within specified tolerances. Fillet weld gage blades are used to check a weld's leg length and throat size.

fillet welds

An approximately triangular weld made to join two surfaces at right angles to each other. Fillet welds are the most common type of welds.

fluorescent

To emit absorbed light. Fluorescent liquids and particles used in testing must be viewed under UV light.

fluoroscopic screen

A screen used to display radiographic images that is lit from behind by fluorescent lights. Fluoroscopic screens allow for immediate viewing of radiographs.

foot-pounds

ft.-lbs. An English unit of measurement used to measure force. One foot-pound indicates the amount of energy needed to move one pound a distance of one foot.

frequency

The rate at which currents or sound waves alternate. Frequency is expressed as the number of cycles per unit of time, such as Hertz (Hz) or cycles per second.

fumes

A potentially hazardous combination of gas and particulate matter. Fumes generated during arc welding processes include particulates from the electrode, shielding gas, base metal, and any coatings.

gamma rays

An electromagnetic wave with a high frequency and short wavelength that is cheaper but less accurate to use in testing. Gamma rays have a greater depth of penetration than X-rays.

grinding wheel

A circular abrasive tool used to wear away material from a surface. Grinding wheels are used to identify metals in spark testing.

groove welds

A weld made in the opening between two parts that provides space to contain weld metal. Groove welds are used on all joints but are less common for lap joints.

guided bend testing

A destructive testing method that bends a welded specimen to determine its strength and durability. Guided bend testing, also known as transverse bend testing, can test the side, face, or root of a weld.

hardness

The ability of a material to resist penetration, indentation, or scratching. Hardness in a metal may change due to the heat generated during welding.

hardness testing

A mildly destructive test that determines how a material responds to external forces that attempt to scratch, penetrate, or indent it. Hardness testing usually involves indenting a material sample and measuring the indentation to determine the material’s hardness value.

HAZ

Heat-affected zone. The portion of the base metal immediately surrounding the weld metal zone. The HAZ does not melt during welding, but its mechanical and physical properties are altered.

heat treatment

A controlled heating or cooling process used to change the structure of a material. Heat treatment alters a material's physical and mechanical properties.

Heat-affected zone

HAZ. The portion of the base metal immediately surrounding the weld metal zone. The heat-affected zone does not melt during welding, but its mechanical and physical properties are altered.

hexapods

A robotic device with six legs that can simulate complex, real-world loading on materials. Hexapods perform fatigue testing along multiple axes.

high-carbon steel

A plain carbon steel that contains more than 0.50% carbon. High-carbon steels are extremely strong and hard, and they always require heat treatment for effective welding.

hydraulic press

A machine that uses pressurized fluid to apply force to an object. Hydraulic presses are often used for destructive weld testing.

hydrochloric acid

A highly corrosive chemical compound that removes oxides from metals. Hydrochloric acid (HCl) is sometimes used in etch testing.

impact strength

A material's ability to resist fracture under sudden force or impact. Impact strength is measured by impact testing, such as Charpy V-notch and Izod tests.

impact testing

A destructive testing method that uses a hammer or other object to strike a weld in order to determine its impact strength and toughness. Impact testing methods include Charpy V-notch testing and Izod impact testing.

impact testing machine

A machine used to determine a material's toughness and strength by striking the material until it breaks. Impact testing machines are used for Charpy V-notch and Izod tests to measure the force required to break a weld specimen.

inclusions

A weld defect in which foreign materials are trapped within the solidified weld metal. Inclusions, such as slag, flux, or tungsten, can compromise the weld's strength and integrity.

incomplete fusion

IF. A discontinuity that occurs when the weld metal and base metal or adjoining weld beads are not fully fused. Incomplete fusion significantly weakens the integrity of a weld.

incomplete joint penetration

IJP. A discontinuity characterized by an unpenetrated and unmelted area in a joint that occurs when weld metal does not extend through the full thickness of the joint. Incomplete penetration can result from insufficient welding heat, improper joint design, and improper lateral control of the welding arc.

incomplete root penetration

A discontinuity characterized by an unpenetrated and unmelted area in a joint that occurs when weld metal does not extend to the root. Incomplete root penetration can be detected with radiographic testing.

indenters

A device that is pressed into a test specimen to evaluate hardness. The indenter leaves a mark in the metal that is measured to determine hardness.

indirect magnetization

Establishing a magnetic field in a part by passing current between two contacts. The yoke method of magnetic particle testing uses indirect magnetization.

Inductively Coupled Plasma Mass Spectrometry

ICP-MS. A type of chemical analysis that uses high-energy argon plasma to precisely measure the elemental composition of a material. Inductively Coupled Plasma Mass Spectrometry separates ions to identify and quantify elements.

iron

A common silvery-white metal found in nature as ore. Iron is alloyed with carbon to make steel.

Izod impact testing

An impact testing method that uses a pendulum hammer to break a vertical test piece that is clamped at the bottom. Izod impact testing strikes the notched side of a weld specimen to measure impact strength.

joint

The meeting point of two materials that are fused together. Welding creates a permanent joint.

joint geometry

The dimensions of a welded joint, including the measurements of the weld face, root opening, and included angle. Joint geometry is specified by fabrication drawings and welding codes.

Knoop hardness testing

A microhardness test that applies a small, diamond indenter shaped like a pyramid with a rhombus base under a load between 10 g and 1 kg for 10 to 15 seconds. Knoop hardness testing can provide the most precise hardness measurements.

laps

A discontinuity characterized by small gaps in the base metal that can form during the steel production process. Laps can be detected by testing, such as electromagnetic and etch testing.

laps

A discontinuity of small gaps in the base metal that can form during the steel production process. Laps can be detected by macro-etch testing.

lifecycle

The series of stages a product goes through during use until it is replaced or fails. The lifecycle of a part can be simulated during fatigue testing.

loads

Force or pressure placed on a material or structure. Parts and welds are designed to be able to withstand certain types and amounts of loads.

low-alloy steels

A steel containing small amounts of alloying elements that are added to change the properties of the metal. Low-alloy steel is strongly magnetic.

low-carbon steel

A plain carbon steel that contains less than 0.15% carbon. Low-carbon steels are generally tough, ductile, and easy to weld.

macro-etch testing

A destructive testing method that involves applying a mildly acidic mixture to a cross-section of a welded joint and examining it for visible flaws. Macro-etch testing can reveal many types of discontinuities and magnifies the surface up to 10x.

magnetic field

The area surrounding magnets and current-carrying conductors that exerts forces of attraction and repulsion. A magnetic field is used to help identify weld defects in magnetic particle inspection.

magnetic particle testing

MT. A nondestructive testing method that uses iron powder or other particles to locate discontinuities in a magnetized workpiece. In magnetic particle testing, discontinuities disrupt the magnetic field and the particles cling to the disrupted areas.

magnetic permeability

The measure of a material's magnetization when a magnetic field is applied. Magnetic permeability can be measured by electromagnetic testing.

magnetic testing

A simple test that involves holding a magnet to a metal and observing the reaction to determine the type of metal. Magnetic testing is not as definitive as chemical analysis.

magnetism

The power of attraction and repulsion between materials. Magnetism most often occurs between ferrous metals.

major load

The larger force applied after the minor load in a hardness test. The major load creates the deeper indentation that is measured to calculate hardness.

martensitic

A stainless steel that contains chromium and small amounts of molybdenum, nickel, and carbon. Martensitic stainless steels are the strongest stainless steels.

material testing

The process of evaluating and identifying the properties of welds and weld materials. Material testing is necessary to ensure weld quality and compliance with welding codes.

mechanical properties

A characteristic that describes how a material responds to forces that attempt to compress, stretch, bend, scratch, dent, or break it. Mechanical properties include strength, hardness, toughness, and ductility.

methanol

A poisonous liquid alcohol that can be used as a solvent. Methanol can be used to help a test piece dry faster in etch testing.

micro-etch testing

A destructive testing method that involves applying a mildly acidic mixture to a cross-section of a welded joint and examining it for visible flaws. Micro-etch testing magnifies the surface above 10x and as high as 100x.

microhardness test

A type of hardness test designed to test very small or brittle materials. Microhardness tests, also known as microindentation tests, involve very light loads.

micrometers

A U-shaped measuring instrument with a threaded spindle that slowly advances toward a small anvil to close around a part. Micrometers provide more precise measurements than calipers.

minor load

The initial, lighter load applied by the indenter in a hardness test. The minor load establishes contact between the indenter and material surface and establishes a reference point for measurement.

NDT

Nondestructive testing. A testing method that does not destroy the workpiece or weld being tested. NDT is ideal for large or expensive workpieces.

nick break testing

A destructive testing method in which small notches are cut into the surfaces of the weld, and the weld is then broken across that slot. Nick break testing allows inspectors to not only measure the strength of a weld but also to examine it for internal defects.

nitric acid

A highly corrosive, colorless or yellowish liquid used in various chemical processes. Nitric acid (HNO₃) is sometimes used in etch testing.

Nondestructive testing

NDT. A testing method that does not destroy the workpiece or weld being tested. Nondestructive testing is ideal for large or expensive workpieces.

overlap

A discontinuity that occurs when the weld metal protrudes beyond the weld toe or weld root. Overlap is nearly always unacceptable in a finished weld.

partial joint penetration

PJP. A weld condition that occurs when the weld metal extends only part of the way through a joint. Partial joint penetration is sometimes desirable to prevent burnthrough.

pendulum hammer

The striking tool of an impact testing machine that applies the force. The pendulum hammer is released at a set position and speed to measure the force of impact.

penetrant

A fluorescent liquid or dye that detects surface flaws. Dye penetrant testing can be used when magnetic tests cannot be used.

penetrant testing

PT. A nondestructive testing method that uses a fluorescent liquid or colored dye to detect and locate surface flaws. Penetrant testing requires an inspector to apply a penetrant and developer to reveal weld discontinuities.

physical properties

A characteristic that describes how a material responds to environmental, electrical, magnetic, and thermal forces. Physical properties include corrosion resistance and conductivity.

poles

The opposite ends of a magnet where the magnetic field is strongest. Poles attract their opposite polarity.

porosity

A weld discontinuity characterized by the appearance of tiny voids in a weld bead, which occurs when gas is trapped in the metal. Excessive porosity can weaken a weld.

porosity

A weld discontinuity characterized by the presence of small cavities on or below the surface of a weld, which occurs when gas is trapped in the metal. Excessive porosity can weaken a weld.

precious metals

A rare, naturally occurring metallic element. Precious metals include gold and silver.

press

A machine with a stationary base and an upper arm that moves along a vertical axis. Presses are often used in fillet weld break testing.

prod method

A magnetic particle testing technique that uses two handheld electrodes, or prods, to create localized, circular magnetic fields on a part. The prod method is best for testing localized areas or harder to access locations and shapes.

properties

A characteristic of a material that distinguishes it from other materials. Properties determine a material's behavior and performance, including how it will react to heavy loads or extreme temperatures.

prototypes

A preliminary model of a product that is tested to evaluate the performance of a design. Prototypes generally undergo testing in different applications and environments to provide specific information about the product.

radiation

Potentially harmful energy emitted in the form of particles or waves. Radiation is emitted during radiographic testing.

radiograph

An image produced by X-rays or gamma rays. Radiograph images can be viewed on film or a fluoroscopic screen.

radiographic testing

RT. A nondestructive testing method that uses electromagnetic waves to reveal the interior of a solid object. Radiographic testing using x-rays or gamma rays.

reduced specimen

A test specimen cut from a welded joint to isolate the area undergoing tensile testing, such as the weld metal. Reduced specimens may have a circular or rectangular cross-section.

reverse bending

A type of loading used in fatigue testing that alternates between tension and compression. Reverse bending subjects a specimen to repeated cycles of bending stress.

rhombus

A four-sided shape with opposite sides that are equal to each other. A rhombus often resembles a diamond.

Rockwell C Hardness scale

HRC scale. A scale used to categorize the hardness of metals in Rockwell hardness testing. The Rockwell C hardness scale assigns higher numbers to greater hardness values.

Rockwell hardness testing

A hardness test that applies a conical diamond indenter called a brale under a maximum load of 150 kg for a duration of 10 seconds or less. Rockwell hardness testing uses different scales for different groups of materials.

shear strength

The ability of a material to resist forces that attempt to cause its internal structure to slide against itself and separate. Shear strength describes the amount of shear stress a material can withstand before fracturing.

slag

A non-metallic byproduct of flux that floats to the top of the molten weld pool and forms a hardened layer on top of the solidified weld metal. Slag protects the cooling metal and is chipped off after the weld has cooled, but it can become trapped inside the finished weld.

slag inclusions

A discontinuity that occurs when flux residue is trapped in the weld metal. Slag inclusions can negatively affect the strength and integrity of a welded joint.

solvent wash

A substance used to clean foreign matter from a part. Solvent wash may be required in some commercial penetrant testing.

sound waves

A vibration, or disturbance, of matter caused by the movement of energy. Sound waves that are above the range of human hearing are used in ultrasonic testing.

spark testing

A simple test that involves holding a metal to a grinding wheel and observing the sparks emitted to determine the type of metal. Spark testing is only used for ferrous metals and cannot replace chemical analysis.

spatter

Liquid metal droplets expelled during the welding process. Spatter can leave undesirable dots of metal on a workpiece surface.

stainless steels

A type of steel that contains 11-30% chromium and exhibits excellent hardness and corrosion resistance. Stainless steel can be welded with many different welding processes.

steel

An alloy of iron and carbon containing less than 2.0% carbon. Steels often contain other elements to enhance various aspects of the metal.

steel rules

A simple measuring instrument consisting of a long, thin metal strip with a marked scale of unit divisions. Steel rules are also called machinist's rules.

straight edges

A flat, rectangular hand tool with a scale of units that can be used to draw straight lines, determine the straightness of a line, or take measurements. A straight edge is used in visual inspection.

strain gages

A device that uses changing electrical resistance to measure the amount of strain within an object. Strain gages are used to measure fatigue strength.

strength

The ability of a material to resist forces that attempt to break or deform it. There are several types of strength, including tensile, compressive, shear, and yield strength.

stress amplitude load

A measurement of the range of stress variations applied to a material or part. Stress amplitude loads represent the variation of stress applied to a weld during fatigue testing.

stress riser

A groove, notch, or other abnormality that concentrates stress in one area and can lead to cracking and failure. Stress risers are used in destructive testing to assist in breaking materials.

sulfuric acid

A highly corrosive, oily acid. Sulfuric acid (H₂SO₄) is sometimes used in etch testing.

tensile failure

The breaking or failing of a material due to stretching or pulling. Tensile failure is more likely to occur in heat-affected zones with high hardness.

tensile strength

The ability of a material to resist forces that attempt to pull it apart or stretch it. Materials with high tensile strength tend to deform, bend, or stretch before breaking.

test plates

A sample weld joint that is used to evaluate welding procedures, welder performance, or material properties. Test plates, also called sample coupons, are welded according to the welding code for a project.

test specimens

A portion of the test plate that is removed and undergoes material testing and inspection. Test specimens often undergo destructive testing, which renders them inoperable.

thermal conductivity

The ability of a material to act as a medium for conveying heat. Materials with high thermal conductivity include aluminum and copper.

T-joint

A joint created between the edge of one part and the surface of a second, perpendicular part that resembles the letter 'T.' T-joints are very common joints that are simple to create.

tolerances

An unwanted but acceptable deviation from a desired dimension that still meets part specifications. Tolerances indicate the allowable difference between a physical feature and its intended design.

toughness

A material's ability to withstand impact without breaking. Toughness generally increases as hardness decreases.

transverse

Situated or extending across the weld. In fillet weld break testing, a load is applied transverse to the welded side of a T-joint.

transverse bend testing

A destructive testing method that bends a welded specimen to determine its strength and durability. Transverse bend testing, also known as guided bend testing, can test the side, face, or root of a weld.

transverse tension testing

A destructive testing method that pulls a weld specimen to determine when it breaks. Transverse tension testing is generally required as part of mechanical testing for groove welds.

ultrasonic flaw detector

An instrument used in ultrasonic testing that uses high-frequency sound waves to detect defects within materials. The ultrasonic flaw detector analyzes and displays reflected sound waves to identify flaws.

ultrasonic probe

A device that converts electrical energy into sound waves or vice versa. Ultrasonic probes, also called ultrasonic transducers, send and receive sound waves to create imaging of the waves and echoes.

ultrasonic testing

UT. A nondestructive testing method that uses high-frequency sound waves to detect internal flaws. In ultrasonic testing, a discontinuity reflects sound waves as an abnormal echo.

ultrasonic transducer

A device that converts one form of energy, such as electrical, into another form of energy, such as mechanical. Ultrasonic transducers, also called ultrasonic probes, convert electrical energy into vibrational sound waves.

ultraviolet light

UV light. Light that is invisible to the naked eye because it consists of very short wavelengths. Ultraviolet light is necessary in order to view fluorescent penetrants and particles.

undercut

A groove melted into the base metal at the weld toe or root that is left unfilled by weld metal. Undercut concentrates stress on the weld and can weaken it.

universal testing machine

A material testing machine used for evaluating tensile and compressive strength. Universal testing machines can perform many standard destructive tests, including transverse tension and guided bend tests.

UV light

Ultraviolet light. Light that is invisible to the naked eye because it consists of very short wavelengths. UV light is necessary in order to view fluorescent penetrants and particles.

variable amplitude testing

A fatigue testing method that applies a range of different loads throughout the testing process. Variable amplitude testing more closely mimics real-world conditions than constant amplitude testing.

ventilation

A means of moving air to remove contaminants and provide clean air. Ventilation reduces the hazards posed by welding fumes and gases.

Vickers hardness testing

A microhardness test that applies a small, diamond indenter shaped like a pyramid with a square base under a maximum load of 120 kg for a duration of 10 to 15 seconds. In Vickers hardness testing, the size of the indentation determines the hardness value.

visual inspection

The visual examination of a part before, during, or after welding to verify quality and uniformity. Visual inspection, or visual testing, is one of the most commonly used nondestructive testing methods for finished welds.

visual testing

VT. The visual examination of a part before, during, or after welding to verify quality and uniformity. Visual testing, or visual inspection, is one of the most commonly used nondestructive testing methods for finished welds.

voltage

A measure of electrical force or pressure that causes current to flow in a circuit. Voltage is measured in volts (V).

VT

Visual testing. The visual examination of a part before, during, or after welding to verify quality and uniformity. VT, or visual inspection, is one of the most commonly used non-destructive testing methods for finished welds.

waveform

The shape of the wave produced by an electrical signal or sound wave. A waveform's shape provides information about the material and weld defects.

weld bead

The end product of a joint that has been welded. Weld beads can be flat, convex, or concave in shape.

weld face

The exposed surface of a weld. The weld face may be convex, concave, or flush with the workpiece.

weld metal

The portion of a weld that has been melted during welding. Weld metal may consist of base metal only or a combination of base metal and filler metal.

weld root

The point at which a weld intersects the surfaces of the base metals opposite the face of the weld. Some welds have openings located at the weld root.

welder performance qualification

WPQ. A test administered to a welder to determine their ability to produce a weld that meets prescribed standards from welding codes. Welder performance qualification tests are specific to a WPS and its requirements.

welder performance qualification record

WPQR. A written record of the materials, welding variables, and test method results of a welder procedure qualification. Welder procedure qualification records are written based off of testing results as they relate to WPS requirements.

welding codes

A collection of standards that outline practices for particular welding applications. Welding codes ensure safe welding practices and high-quality welded products.

Welding Procedure Specifications

WPSs. A formal, written document detailing specification for a welding procedure, including specified processes, materials, techniques, and variables. A welding procedure specification must be approved and tested before it can be used.

weldment

A welded joint. Weldments are tested for defects and discontinuities.

weld-size gages

A metal tool that measures a part feature or weld bead to determine whether or not it is within a specified limit or tolerance. A weld-size gage is one of the main tools used in visual inspection.

WPQ

Welder Performance Qualification. A test administered to a welder to determine their ability to produce a weld that meets prescribed standards from welding codes. WPQ tests are specific to a WPS and its requirements.

WPSs

Welding procedure specifications. A written document that contains all the specific information necessary for completing a weld. A WPS must be approved and tested before it can be used.

X-ray Fluorescence

XRF. A type of chemical analysis that uses X-rays to identify the elemental composition of a material. X-Ray Fluorescence identifies materials by their reaction to X-rays.

X-rays

An electromagnetic wave with a high frequency and short wavelength used most commonly in radiographic testing due to accuracy. X-rays are used to view the interior of solid objects in radiographic testing.

yield strength

The ability of a material to tolerate gradual, progressive force without permanent deformation. Yield strength is the stress level where the material transitions from reversible to permanent deformation.

yoke method

A magnetic particle testing technique that uses a handheld electromagnetic yoke to establish a magnetic field. The yoke method is powered by alternating or direct current.

zinc

A bluish-white metal that is corrosion resistant and has a relatively low melting point. Zinc is often used as a protective coating on steel.