Stolk Labs, Inc. offers a wide range of mechanical testing services to evaluate metals, steel, plastics, polymers, adhesives, coatings, and composites. Whether you require a material’s mechanical properties or to determine the response of a material to a given action, we are here to help!
Our materials testing portfolio includes routine mechanical testing, such as hardness testing and tensile testing, as well as advanced and custom mechanical testing techniques. Certified technicians prepare specimens, provide testing, and report data within three to five business days. Options for expedited services are available.
Mechanical Testing of Materials
Precise Test Specimens for Accurate Test Results
Repeatable test results begin with good sample blanks and tight tolerance machining techniques. Stolk Labs offers wet or dry condition cutting and tooling for metals, polymers, or composites. A hospital-clean environment translates into fine surface finishes. Double doors and a fork lift can accommodate large crates or heavy industrial parts. Doors between laboratories are placed as to easily move tall or wide parts into the next room for testing. Sectioning procedures are contained in a room with negative pressure to negate industrial odors and debris.
Accredited Mechanical Testing Services
Stolk Lab’s offers a variety of mechanical testing services, performed by our team of experts. We are ISO/IEC 17025:2017 accredited through PJLA in the following mechanical testing services:
- Rockwell hardness of plastics and metallic materials
- Brinell hardness and Light Load Brinell hardness of metallic materials
- Knoop microhardness, Vickers microhardness and Heavy Load Vickers microhardness of metals and other materials
- Durometer hardness of plastics and rubber
- Bend testing of metals, plastics and welds (ductility of material and ductility of welds)
- Compression testing of metallic materials
- Tension testing/Tensile test of metallic materials, wrought, cast aluminum and magnesium-alloy products
Sub-size Tensile of metals/metallic materials - Shear testing/Shear strength of metals, plastics and adhesives
Proof load of steel products and fasteners - Flexural properties of (unreinforced and reinforced) plastics and polymers (polymer matrix composite materials)
- Finish adhesion on coatings
- Impact testing on metals (Charpy impact)
Hardness Testing
Hardness enables a material to resist plastic deformation, penetration, indentation, and scratching. The hardness of a material is measured by indenting the surface with a smaller indenter (loaded object) made from a harder material. The indentions are measured and reported based on the client’s required scale (i.e. Rockwell C – HRC, Rockwell B – HRB, 15T – Superficial Rockwell, Knoop – KV, Brinell – HB, Durometer Shore A – HA). The hardness of a material is dependent upon ductility, elastic stiffness, plasticity, strain, strength, toughness, viscoelasticity, and viscosity. The harder a material is the more likely the chances it will withstand routine wear by friction or erosion.
Surface Hardness Testing:
Rockwell Hardness Testing
Rockwell hardness testing is the most commonly used method of hardness testing and is considered a non-destructive technique. It measures the depth of penetration of an indenter under a large load compared to the penetration made by a preload. The result is noted as HRA, HRB, HRC, etc. The last letter represents the Rockwell scale. Rockwell hardness testing is used on most metals. Exemptions happen when the sample size or shape prevents use of the Rockwell hardness tester, the indentions are too large for the sample, or the surface structure/conditions would introduce too many variations. Rockwell hardness testing may also be used on harder plastics like nylon, polycarbonate, polystyrene, and acetal (polyoxymethylene).
Other common search terms: Rockwell A hardness testing, Rockwell B hardness testing, Rockwell C hardness testing, Rockwell hardness testing on metal, Rockwell hardness testing on plastic, Rockwell superficial hardness testing
ACCREDITED ROCKWELL HARDNESS TESTING SERVICES:
Standard Test Methods and Definitions for Mechanical Testing of Steel Products – ASTM A370
Standard Test Method for Rockwell Hardness of Plastics and Electrical Insulating Materials – ASTM D785
Standard Test Methods for Rockwell Hardness of Metallic Materials – ASTM E18
Brinell Hardness Testing
Brinell hardness testing is used to test the hardness of metals and alloys (non-homogenous materials/castings). It measures the depth of penetration of an indenter (hard ball) loaded on a material surface by hydraulically pressing under a standard load. While Rockwell hardness is directly readable, Brinell requires optical evaluation and measurement of the indent. The result is shown as a ratio of load and area of indention, then noted as HB (Hardness Brinell). Brinell hardness can be used on thin specimens of very hard materials, but can also deform materials when testing in micro range with very high test loads.
Other common search terms: hardness testing on castings, hardness testing on forgings, casting hardness testing, forging hardness testing, HB testing, HBw testing
ACCREDITED BRINELL HARDNESS TESTING SERVICES:
Standard Test Method for Brinell Hardness of Metallic Materials – ASTM E10
Standard Test Methods and Definitions for Mechanical Testing of Steel Products – ASTM A370
ACCREDITED LIGHT LOAD BRINELL HARDNESS TESTING SERVICES:
Standard Practice for Rapid Indentation Hardness Testing of Metallic Materials – ASTM E103
Microhardness Testing
Microhardness testing is a hardness testing method used when test samples are very small, thin or plated. It is also used on composite samples when small areas are to be measured. This can be done on the surface of a sample all the way to the core. An indentation is made on the specimen by a diamond indenter and the indentation is measured with the help of an optical microscope. After using a special formula, results are reported as HV (Hardness Vickers) or HK (Hardness Knoop).
Other common search terms: Vickers hardness testing, hardness Vickers testing, Vickers microhardness testing, HV testing, Knoop hardness testing, hardness Knoop testing, Knoop microhardness testing, HK testing
ACCREDITED MICROHARDNESS TESTING SERVICES:
- Knoop or Vickers
Standard Test Method for Microindentation Hardness of Materials – ASTM E384
- Heavy Load Vickers
Standard Test Method for Microindentation Hardness of Materials – ASTM E384
Standard Test Methods for Vickers Hardness and Knoop Hardness of Metallic Materials – ASTM E92
Durometer Hardness Testing
Durometers are used to measure the hardness of plastics (polymers, elastomers) and rubbers. Different Shore hardness scales are used to measure a materials resistance to indention. The higher the numbers are on the scale, the greater the material’s resistance to indentation (harder materials). The lower the numbers are on the scale, the less the material’s resistance to indentation (softer materials).
Other common search terms: Rubber hardness testing, hardness testing on rubber, plastic hardness testing, hardness testing on plastic, rubber O-ring hardness testing, hardness testing on rubber O-rings, rubber gasket hardness testing, hardness testing on rubber gaskets, Shore A hardness testing, Shore D hardness testing, HA hardness testing, HD hardness testing
ACCREDITED DUROMETER TESTING SERVICES:
- (Rubber and/or Plastic) Hardness
Standard Test Method for Rubber Property—Durometer Hardness – ASTM D2240
Universal Test Machine Mechanical Tests:
When materials are odd dimensions a custom holding fixture must be made. Custom testing can be provided but must be communicated before a job can be approved. Give us a call so we can make sure we meet your needs!
Flexure Test
Flexure testing involves placing a material under three types of fundamental stress: tensile, compression and shear all at the same time. This technique measures the force required to bend a material and determines the material’s resistance to flexing (stiffness). The sample is laid horizontally over a lower support span which provides two points of contact. A force is then applied to the top of the sample at one point or two points of contact until it fails. The maximum recorded force is the flexural strength of the material.
Other common search terms: 3-point flexure test, 4-point flexure test, custom flexure testing, aluminum extrusion flexure testing, flexure testing lab
ACCREDITED FLEXURE TESTING SERVICES:
Standard Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating Materials – ASTM D790
Standard Test Method for Flexural Properties of Polymer Matrix Composite Materials – ASTM D7264-D7264M
Bend Test
Bend testing is a type of flexural test and is typically used to evaluate the reaction or behavior of materials to realistic loading situations (simple beam loading). This simple test shows a materials ductility. A test coupon is bent in three point or four point bending with uniform stress to a specific angle. Any cracks or inconsistencies on the outer surface (outer bent area) are reported.
Other common search terms: 3-point bend test, 4-point bend test, custom bend testing, aluminum extrusion bend testing, bend testing lab, weld qualification bend testing, weld procedure bend testing, bend testing for weld qualification, bend testing on welded vessel, bend testing on welded material
ACCREDITED BEND TESTING SERVICES:
Standard Test Methods and Definitions for Mechanical Testing of Steel Products – ASTM A370
Standard Test Methods for Bend Testing of Material for Ductility – ASTM E290
Standard Test Method for Guided Bend Test for Ductility of Welds – ASTM E190
Compression Test
Compression testing is a technique in which a material is subjected to opposing forces pushing inward upon it from opposite sides (compressed, crushed, squashed, flattened). Compression testing is usually done to a break (rupture) or to a client requested or specified limit. Results indicate the material’s ability to recover after the compressive force is applied and held over a designated period of time.
Other common search terms: custom compression testing, compression testing lab, material compression testing, compression testing on metal, compression testing on steel, metal compression testing
ACCREDITED COMPRESSION TESTING SERVICES:
Standard Test Methods of Compression Testing of Metallic Materials at Room Temperature – ASTM E9
Tensile Test and Sub-size Tensile Test / Tension Test
Tensile testing is a destructive testing technique in which a material (metals, plastics, elastomers, textiles, composites, adhesives) is subjected to a controlled pulling force until failure. This determines how strong and how much the material can elongate (make longer in relation to its width; stretched before it breaks). Based on the client’s needs, we can provide ultimate strength, yield strength, ductility, peak load and failure location in tabled results.
Sub-size tensile testing is provided on a case-by-case basis. Specimens must be a minimum of 2 inches long in order to test without providing a custom fixture or welding service. Results are reported based on client needs just like routine tensile testing.
Other common search terms: tensile testing lab, metal tensile testing, tensile testing on metal, tensile testing on sheet metal, tensile testing on plastic, polymer tensile testing, steel tensile testing, material tensile testing, custom tensile testing, tension test lab
ACCREDITED TENSILE TESTING/TENSION TESTING SERVICES:
Standard Test Methods and Definitions for Mechanical Testing of Steel Products – ASTM A370
Standard Test Methods for Tension Testing of Metallic Materials – E8/E8M
Standard Test Methods for Tension Testing Wrought and Cast Aluminum- and Magnesium-Alloy Products – ASTM B557
Standard Test Method for Tensile Properties of Plastics – ASTM D638
ACCREDITED SUB-SIZE TENSILE TESTING SERVICES:
Standard Test Methods for Tension Testing of Metallic Materials – E8/E8M
Shear Test
Shear testing is similar to tension testing, but applies force to a material in a parallel (sliding) direction instead of holding it in tension. This technique is typically used on two materials that have been joined together by some type of adhesive or weld.
Other common search terms: lap shear testing, lap-shear test, lap shear testing of adhesives, shear strength adhesive testing, shear strength testing, Single lap shear testing, Double lap shear testing, shear testing lab, shear testing on metal coupons
ACCREDITED SHEAR TESTING SERVICES:
Standard Test Method for Apparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Tension Loading (Metal-to-Metal) – ASTM D1002
Standard Test Method for Shear Testing of Aluminum Alloys – ASTM B769
Standard Test Method for In-Plane Shear Strength of Reinforced Plastics – ASTM D3846
Standard Test Method for Measuring Strength and Shear Modulus of Nonrigid Adhesives by the Thick-Adherend Tensile-Lap Specimen – ASTM D3983
Proof Load Test
Proof load testing is important for structural and safety guarantees on equipment used for carrying, supporting, rigging and/or lifting. From basic office supplies to heavy cranes, this testing technique helps determine whether or not the equipment or material is able to hold the maximum weight (capacity) it was made to hold without breaking or malfunctioning (maximum weight bearing capabilities). Proof load testing should be conducted before any lifting or supporting device is placed into service.
ACCREDITED PROOF LOAD TESTING SERVICES:
Standard Test Methods and Definitions for Mechanical Testing of Steel Products – ASTM A370
Standard Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners, Washers, Direct Tension Indicators, and Rivets – ASTM F606/F606M
Impact Test
Charpy impact testing is a standardized high strain-rate test that determines the amount of energy absorbed by a material during fracture. A hammer on a swinging pendulum arm is used to strike a notched specimen held tightly at each end. The hammer strikes opposite the notch and the energy absorbed by the sample is determined by precisely measuring the decrease in motion of the pendulum arm. Results are provided in a table format that shows the different areas (zones) of a larger piece of material (i.e. weld, base metal, heat affected zone) the samples were cut from.
Other common search terms: impact testing on vessel, impact testing on welded material, Charpy impact testing lab, impact testing of metals, steel impact testing, Charpy impact testing for weld qualification, ASME Charpy impact testing
ACCREDITED IMPACT TESTING SERVICES:
- Charpy Machine (ambient temperature)
Standard Test Methods for Notched Bar Impact Testing of Metallic Materials – ASTM E23
*We also provide Charpy Impact Testing (sub-zero temperature) at client’s request and with provided specifications.
Coating Finish Adhesion Test
It is important to test the adhesion of coatings to the underlying substance or layer. One way of assessing this is by applying and removing pressure-sensitive tape over cuts made in the film (coating). The method used is based on the thickness of the finish and where the testing is taking place (i.e. job site or laboratory). Results are presented in rating scale fashion.
ACCREDITED FINISH ADHESION TESTING SERVICES:
Standard Test Methods for Rating Adhesion by Tape Test – ASTM D3359
We serve manufacturing, aerospace, automotive, legal, biomedical, oil and gas, power generation, microelectronics and telecommunications industries and sectors. Don’t see your industry listed here? Give us a call. Our goal is to help you produce a reliable product that withstands its environment and meets industry standards.
ISO/IEC 17025:2017 Accredited
Review our Certificate and Scope of Accreditation. Feel free to download and save for your records.
PJLA-certificate-of-accreditation
With our vast industry experience, Stolk Labs, Inc. offers our professional services for subrogation/claims investigations.
- Joint Investigations
- Joint Inspections
- Fire Investigations
- Insurance Investigations
- Product Liability Investigations
- Equipment Defect Investigations
Call and schedule your tour today!