Solving Material Characterization Challenges with a UTM.

A key function of a universal testing machine is to perform tests in accordance with globally recognized standards to ensure that results are comparable and compliant. There are hundreds of such standards. For plastics, one of the most common tensile test standards is ASTM D638 or the very similar ISO 527. For metals, ASTM E8 is the fundamental standard for tensile testing. For compression testing of polymers, ASTM D695 is often used. Flexural properties are commonly tested using ASTM D790. These standards dictate everything from the shape and size of the test specimen to the speed of the test and how the results should be calculated. The software on a WBE universal testing machine comes with pre-configured modules for these and many other standards to simplify compliance.

To ensure the ongoing accuracy and reliability of your universal testing machine, a regular schedule of calibration and maintenance is essential. Calibration is the process of verifying the machine's measurement systems (force, displacement, and strain) against a traceable reference standard. This is typically done annually by an accredited service technician and is crucial for maintaining quality certifications and data integrity. Maintenance involves routine checks and servicing of the machine's mechanical and electrical systems. This includes inspecting drive belts, lubricating lead screws, checking for worn grips, and ensuring all safety features are functioning correctly. A proactive approach to calibration and maintenance, like the service plans offered by WBE for our universal testing machine lineup, is the best way to protect your investment and ensure consistent, trustworthy test results.

Selecting the correct force capacity is the most critical decision when purchasing a universal testing machine. The capacity is the maximum force the machine can safely apply. To determine your required capacity, you must first identify all the materials you plan to test and find their estimated ultimate strengths. Your machine's capacity must be greater than the breaking force of your strongest material. However, it is also important not to oversize the machine excessively. The load cell, which measures the force, is most accurate in the middle of its range. If you are consistently testing very low-force samples on a very high-capacity machine, your accuracy may be compromised. In many cases, it is best to purchase a universal testing machine with a capacity for your strongest materials and then buy an additional, lower-range load cell that can be easily swapped in for more sensitive tests.

A universal testing machine (UTM) is a foundational piece of equipment in materials science and quality control. Its primary job is to determine the mechanical properties of materials and components by applying a controlled force. The machine's powerful drive system moves a crosshead up or down at a precise speed. This movement applies a force to a specimen that is held in place by specialized grips or fixtures. A highly accurate sensor called a load cell measures the applied force, while an extensometer or the crosshead position measures the specimen's deformation or stretch. This data is plotted on a graph, typically a stress-strain curve, from which critical properties like strength, stiffness, and ductility are determined. Its "universal" capability allows it to perform various tests, such as pulling (tensile), pushing (compression), and bending (flexural).