Destructive Testing Services and Accredited Mechanical Laboratory Solutions

In industrial manufacturing, the production of pressure equipment, and the construction of steel structures, knowing merely the surface quality of materials is insufficient. The only way to determine how materials and welded joints behave under actual loads—and to measure yield and tensile limits, fracture energy, and microstructural stability—is to push the material to its limits. Destructive Testing is the most definitive laboratory methodology for revealing actual strength limits through numerical data by subjecting the material to mechanical or metallurgical deformation.

Leveraging an advanced laboratory infrastructure fully compliant with international accreditation standards (ISO, EN, ASME, AWS) and a team of expert metallurgical engineers, our engineering and inspection organization provides end-to-end accredited mechanical testing services for your welding procedure qualifications (WPS/PQR), welder certification tests, and material verification processes.

1. What is Destructive Testing and Why Is It Mandatory?

Destructive testing is the process of subjecting standard samples (coupons) taken from a material or a welded joint to mechanical forces until they fracture, rupture, or bend completely. While Non-Destructive Testing (NDT) identifies existing defects in a part, destructive testing verifies the material's chemical and physical limits.

Key Areas Where Mechanical Testing Is Critical:

• Welding Procedure Qualification Records (PQR): Performing mechanical tests is a legal requirement to validate a new welding procedure in accordance with TS EN ISO 15614 or ASME Sec. IX standards.
• Welder Qualification Testing (WQT): This is the process of mechanically verifying (via bending, breaking, etc.) the manual skills and weld quality of welders under TS EN ISO 9606-1 and ASME Sec. IX standards.
• Material Acceptance and Verification (EN 10204): Laboratory testing to verify whether steels, castings, or forged parts intended for production meet the mechanical property values ​​specified in the manufacturer's certificate (3.1 or 3.2 certification).

2. Key Mechanical Test Methods Offered at Our Accredited Laboratory

The destructive testing methods we perform using highly precise, calibrated equipment—in accordance with your project's technical specifications and international standards—are as follows:

2.1. Tensile Testing

This process involves pulling a material or weld seam under an axial load until fracture occurs. Through this test, the material's Yield Strength, Tensile (Ultimate) Strength, and percentage elongation/reduction of area values ​​are graphically determined. For welded joints, transverse tensile tests are conducted in accordance with the TS EN ISO 4136 standard to verify whether the weld possesses greater strength than the base material.

2.2. Bend Testing

This process involves bending welded coupons—at the face, root, or side—up to 180 degrees around a mandrel of a specified diameter (TS EN ISO 5173). The objective is to measure the ductility of the weld seam and the heat-affected zone (HAZ), as well as to reveal any micro-cracks or lack-of-fusion defects that may occur during bending.

2.3. Charpy Impact Testing

This is the most critical test performed to measure a material's resistance to dynamic loads and its tendency toward brittle fracture (TS EN ISO 148-1). Specimens featuring V- or U-shaped notches—typically cooled to low temperatures such as -20°C, -40°C, or -196°C—are fractured in a single blow using a pendulum hammer. The material's toughness is determined by calculating the energy absorbed (in Joules) during the fracture process.

2.4. Hardness Testing and Hardness Scanning

This involves measuring a material's resistance to plastic deformation. Hardness measurements are conducted in our laboratory using Brinell (HB), Rockwell (HRC/HRB), and Vickers (HV) methods. Particularly in welded fabrications, linear hardness scanning is performed across the base material, the Heat-Affected Zone (HAZ), and the weld metal in accordance with the TS EN ISO 9015-1 standard to check for the formation of brittle, hard structures resulting from heat input.

2.5. Fracture Test (Break Test)

This test is used—particularly for fillet welds—to assess the welder's penetration quality (TS EN ISO 9017). The welded specimen is fractured by applying force in the opposite direction, and the fracture surface is macroscopically examined for root defects, porosity, slag inclusions, or lack of fusion.

2.6. Macroscopic and Microscopic Examination (Metallurgical Analysis)

• Macro Examination (TS EN ISO 17639): This process involves cutting and grinding the weld cross-section and etching it with special chemical acids. Using the naked eye or a low-magnification microscope, features such as the weld pass sequence, root penetration, undercut, and Heat-Affected Zone (HAZ) boundaries are clearly examined and photographed.
• Micro Examination: An analysis performed under high-magnification metallurgical microscopes to examine the material's grain structure, phase distributions (ferrite, pearlite, martensite, etc.), inclusion content, and microstructural defects.

3. Comparative Mechanical Test Matrix

The table below summarizes which tests are used in your manufacturing processes to verify specific mechanical characteristics:

4. Personnel Certification and Reporting Reliability

All tests conducted in our mechanical laboratory are monitored in accordance with international quality standards, covering everything from equipment calibration data to sample preparation precision. Preparing test specimens to standard dimensions (e.g., Charpy V-Notch coupons) using our CNC and precision milling machines is the most critical parameter directly affecting the accuracy of test results.

Mechanical test reports issued by our laboratory are accepted as official evidence and approval documentation during legal inspections, audits by Notified Bodies under the Pressure Equipment Directive (PED) 2014/68/EU, and across all international projects.

5. Frequently Asked Questions (FAQ) About Destructive Testing

Which destructive tests are mandatory for PQR approval?

Requirements vary depending on the standard (e.g., TS EN ISO 15614-1) and material thickness. However, for the butt-weld PQR approval of steel plates thicker than 3 mm, the basic requirements generally include 2 transverse tensile tests, 2 face bend tests, 2 root bend tests, macro-examination, and hardness testing. If the thickness is 12 mm or greater, notch impact tests are also added to the list.

Why is it important to prepare specimens in accordance with standards?

Mechanical testing equipment applies very high forces. Even millimetric deviations in specimen dimensions distort cross-sectional area calculations (cross-sectional area = width x thickness), resulting in completely erroneous yield and tensile strength values ​​(expressed in MPa). Therefore, all test coupons must be professionally machined within the tolerances prescribed by accredited standards.

Why is destructive testing preferred for welder certification exams?

Although radiographic testing (RT) indicates weld quality, it may not fully measure root penetration, particularly in fillet welds. Break tests or macro-etch tests provide 100% certainty in verifying whether the weld metal has fully fused with the base material (detecting issues such as lack of fusion or "cold laps").

Fast and Reliable Laboratory Services for Your Projects

Incorrect or incomplete mechanical testing can lead to the revocation of your PQR approvals, the invalidation of welder certifications, and—most critically—structural failures in the field after manufacturing. To eliminate project risks and obtain accredited reports with highly accurate technical data in the shortest possible time, contact our team of expert engineers today, and let us professionally manage your mechanical testing processes.