Tensile testing service

Tensile Testing Service – Comprehensive Evaluation of Mechanical Properties for Metals, Polymers, Composites and Advanced Materials

As an ISO/IEC 17025 accredited independent testing laboratory, we offer specialised tensile testing services to manufacturers, engineering contractors, and quality assurance teams across the automotive, aerospace, construction, oil and gas, medical device, and general manufacturing sectors. Tensile testing – also known as tension testing – is one of the most fundamental and widely used mechanical test methods for evaluating the strength, ductility, and elastic properties of materials under uniaxial tensile loading. By applying a controlled, increasing tensile force to a standardised test specimen, we determine critical material properties including yield strength, ultimate tensile strength, elongation, reduction of area, and modulus of elasticity. Our test protocols are executed in accordance with ASTM E8/E8M (Metallic materials – Tension testing), ISO 6892‑1 (Metallic materials – Tensile testing – Part 1: Method of test at room temperature), ASTM D638 (Tensile properties of plastics), ISO 527 (Plastics – Determination of tensile properties), EN 10002 (Metallic materials – Tensile testing), and GB/T 228.1 (Metallic materials – Tensile testing). Our inspection and test reports are recognised by the National Medical Products Administration (NMPA), the State Administration for Market Regulation (SAMR), the Ministry of Industry and Information Technology (MIIT), and international certification bodies for product registration, type approval, and quality assurance.

Materials and Products We Regularly Test

Our tensile testing facilities accommodate a wide range of material types, product forms, and finished components. Typical test articles include:

Metals and alloys – carbon steels, stainless steels, aluminium alloys, titanium alloys, copper alloys, nickel‑based alloys, and superalloys
Polymers and plastics – thermoplastics (ABS, PC, PA, PP, PE, PS), thermosets (epoxy, phenolic), elastomers (rubber, silicone), and engineering plastics
Composite materials – glass fibre reinforced plastics (GFRP), carbon fibre reinforced plastics (CFRP), and hybrid composites
Welded assemblies and weldments – including weld metal, fusion line, and heat‑affected zone (HAZ) testing
Fasteners – bolts, screws, studs, and nuts
Wire, cable and rod products – steel wire, aluminium wire, and copper wire
Pipe and tubing – seamless and welded pipes, tubes, and hollow sections
Films, sheets and laminates – polymer films, metal sheets, and laminated composites
Finished components and production samples – for quality control and material certification

Tensile Properties – Yield Strength, Tensile Strength, Elongation and Modulus

Yield strength (YS) – the stress at which the material begins to deform plastically – ASTM E8 / ISO 6892‑1 / GB/T 228.1 – We determine the yield strength using the offset method (typically 0.2 % offset for metals) or the extension‑under‑load method (for materials with a well‑defined yield point). The yield strength is a critical design parameter for structural components, indicating the maximum stress that the material can withstand without permanent deformation. The result is reported in MPa or ksi.
Ultimate tensile strength (UTS) – the maximum stress that the material can withstand – ASTM E8 / ISO 6892‑1 / GB/T 228.1 – The ultimate tensile strength is the maximum tensile stress recorded during the test, up to the point of necking. It is a measure of the material's overall strength and is commonly used for material comparison and quality control. The result is reported in MPa or ksi.
Elongation at break – the percentage increase in length at fracture – ASTM E8 / ISO 6892‑1 / GB/T 228.1 – We measure the elongation at break (or the percentage elongation) by comparing the gauge length of the specimen before and after the test. It is a measure of the material's ductility – the ability to deform plastically before fracture. A high elongation (> 20 %) indicates good ductility; a low elongation (< 5 %) indicates a brittle material.
Reduction of area (RA) – the percentage reduction in cross‑sectional area at fracture – ASTM E8 / ISO 6892‑1 / GB/T 228.1 – We measure the reduction of area by comparing the cross‑sectional area at the fracture surface with the original cross‑sectional area. It is a measure of the material's ductility, particularly for metals. A high RA (> 40 %) indicates good ductility.
Modulus of elasticity (Young's modulus) – the stiffness of the material – ASTM E8 / ISO 6892‑1 / GB/T 228.1 – We calculate the modulus of elasticity from the initial linear portion of the stress‑strain curve. It is a measure of the material's stiffness – the resistance to elastic deformation. The modulus is expressed in GPa (or Msi). A high modulus indicates a stiff material; a low modulus indicates a flexible material.
Poisson's ratio – the ratio of transverse to axial strain – ASTM E132 / ISO 527 – For some materials, we measure Poisson's ratio by monitoring the transverse strain during the tensile test. It is a measure of the material's volume change under loading.

Tensile Test Methods – Room Temperature, Elevated Temperature and Sub‑Zero Testing

Room‑temperature tensile test – ASTM E8 / ISO 6892‑1 / GB/T 228.1 – for standard material characterisation – The test is performed at standard laboratory conditions (typically 20‑25 °C, 50 % RH). The specimen is pulled at a controlled crosshead speed (or strain rate) until failure. The stress‑strain data is recorded continuously, and the key tensile properties are determined.
Elevated‑temperature tensile test – ASTM E21 / ISO 6892‑2 / GB/T 228.2 – for high‑temperature applications – For materials used in high‑temperature environments (e.g., power generation, aerospace), we perform tensile tests at elevated temperatures (up to 1 000 °C) using a furnace attached to the testing machine. The test is performed at the specified temperature, and the tensile properties are compared to the room‑temperature values. A significant reduction in yield strength (> 30 %) is typically observed at elevated temperatures.
Sub‑zero tensile test – ASTM E1450 / ISO 6892‑1 – for cold‑climate and cryogenic applications – For materials used in cold environments (e.g., polar regions, cryogenic storage), we perform tensile tests at sub‑zero temperatures (down to -196 °C) using a temperature‑controlled chamber. The test assesses the ductile‑to‑brittle transition behaviour and the change in tensile properties at low temperatures.
Strain‑controlled tensile test – ASTM E8 / ISO 6892‑1 – for assessing the strain‑hardening behaviour – In addition to the standard force‑controlled test, we perform a strain‑controlled test (using an extensometer) to accurately measure the strain at yield and to determine the strain‑hardening exponent (n‑value). The n‑value is an important parameter for materials that undergo significant plastic deformation during forming.

Test Specimen Preparation – Ensuring Consistency and Representative Results

Specimen machining – to the specified dimensions and surface finish – ASTM E8 / ISO 6892‑1 / GB/T 228.1 – We machine the tensile specimens from the supplied material (plates, bars, sections, or finished products) to the specified dimensions. The specimens are prepared with a uniform gauge section and threaded or shouldered ends for gripping. The gauge length is marked on the specimen, and the cross‑sectional area is measured precisely.
Specimen orientation – longitudinal, transverse, and through‑thickness – for assessing anisotropy – For materials with directional properties (e.g., rolled plates, forgings), we prepare specimens in the longitudinal (L), transverse (T), and through‑thickness (S) orientations, as required by the specification. The orientation is marked on the specimen and reported in the test results.
Specimen conditioning – for plastics and polymers – ISO 291 / ASTM D618 / GB/T 2918 – For plastics, the specimens are conditioned at 23 °C and 50 % RH for a minimum of 48 hours before testing. The conditioning ensures that the material properties are stable at the start of the test.
Specimen inspection – for dimensional accuracy and surface defects – Before testing, we inspect the specimens for any surface defects (scratches, pits, or burrs) that could act as stress raisers. The gauge length and the cross‑sectional area are measured accurately, and the specimen is weighed (if required).

Data Analysis and Interpretation – Quantifying Tensile Performance

Stress‑strain curve – the primary output of the tensile test – The stress‑strain curve (engineering stress vs. engineering strain) is recorded for each specimen. The curve provides a complete picture of the material's elastic and plastic behaviour – from the initial elastic region to the yield point, the strain‑hardening region, and the final fracture.
Offset yield strength (0.2 % offset) – for materials without a well‑defined yield point – For materials that do not have a clear yield point (e.g., aluminium, copper), we determine the yield strength using the 0.2 % offset method. The offset line is drawn parallel to the initial linear portion of the stress‑strain curve, and the intersection point with the stress‑strain curve gives the yield strength.
True stress‑true strain curve – for advanced analysis and material modelling – From the engineering stress‑strain data, we calculate the true stress (force divided by the instantaneous cross‑sectional area) and the true strain (the natural logarithm of the ratio of the instantaneous length to the original length). The true stress‑true strain curve is used for finite element analysis (FEA) and for the development of material models.
Statistical analysis – for batch‑to‑batch consistency and material qualification – For multiple specimens, we report the mean, standard deviation, and coefficient of variation (CV) of the key tensile properties (yield strength, ultimate tensile strength, elongation). A CV of less than 5 % indicates excellent consistency; a CV of less than 10 % is considered acceptable for most materials.

Regulatory Compliance and Product Certification – Supporting Industry Standards

Our tensile testing services are performed in accordance with the most widely used international and national standards. The most commonly requested include:

ASTM E8/E8M – Standard Test Methods for Tension Testing of Metallic Materials – the primary standard for tensile testing of metals in North America
ISO 6892‑1 – Metallic materials – Tensile testing – Part 1: Method of test at room temperature – the international standard for tensile testing of metals
ASTM D638 – Standard Test Method for Tensile Properties of Plastics – for tensile testing of plastics
ISO 527 – Plastics – Determination of tensile properties – the international standard for tensile testing of plastics
EN 10002 – Metallic materials – Tensile testing – the European standard for tensile testing
GB/T 228.1 – Metallic materials – Tensile testing – Part 1: Method of test at room temperature – the Chinese national standard for tensile testing of metals
ASTM E21 – Standard Test Methods for Elevated Temperature Tension Tests of Metallic Materials – for elevated‑temperature tensile testing
ISO 6892‑2 – Metallic materials – Tensile testing – Part 2: Method of test at elevated temperature – for elevated‑temperature tensile testing

Report Acceptance and Regulatory Recognition

All tensile tests are conducted under our ISO/IEC 17025 accreditation, using calibrated universal testing machines, extensometers, and environmental chambers, all traceable to national and international reference standards. Our final test reports include: a complete description of the test article (material, dimensions, orientation, manufacturer), the test method and conditions (temperature, strain rate, humidity), the measured parameters (yield strength, ultimate tensile strength, elongation, reduction of area, modulus of elasticity), the stress‑strain curve (graphical representation), a statistical summary (mean, standard deviation, coefficient of variation), and a clear pass/fail verdict against your specified acceptance criteria. These reports are accepted by the National Medical Products Administration (NMPA), the State Administration for Market Regulation (SAMR), the Ministry of Industry and Information Technology (MIIT), and international certification bodies for product registration, type approval, and quality assurance. Bilingual (English/Chinese) versions are available to facilitate submissions to domestic and international authorities and to support your global market access.