CMTL - Mechanical Testing

Mechanical Testing
The mechanical testing lab at CMTL can perform a complete range of metal and polymer evaluations from simple hardness tests to sophisticated computer controlled cycle tests. Stress-Strain Properties Our computer controlled universal testing machines are programmed to evaluate the stress/strain properties of metal, rubber and plastic. Tensile, compression and flexural property testing to ASTM specifications are standard test procedures specific to your needs. The 20" extensometer and 84" of travel on one of these machines allow us to test polymers having an excess of 1,000% elongation. Our universal testing machines have load capacities up to 120,000 lbf enabling us to test large as-cast or full size specimens. Fasteners can be evaluated for shear strength, proof load strength, surface and core hardness, and wedge tensile strength.
Formability The formability of sheet steel can be evaluated by testing for the strain-hardening exponent (n value) and the plastic strain ratio (r value). Parts formed from steel sheet whose "n" value is low may undergo excessive thinning and fracture in critical regions. Identical parts formed from from a sheet with a higher strain-hardening exponent will be strong enough in the critical areas to transfer strain to adjacent areas, thereby avoiding failure during forming.
Notched Bar Impact Testing Impact tests on notched specimens are used to predict the likelihood of brittle fracture at a specified temperature. CMTL performs both Charpy (simple beam) and Izod (canti-lever beam) impact testing on metal specimens at any test temperature from -321慚 to +1800慚. Plastics and electrical insulating materials can be evaluated for their resistance to breakage by flexural shock testing for notched or unnotched Izod impact strength using our computer controlled machine. Hydrogen Embrittlement Relief Lever arm testers are used in the testing of plated parts and test specimens to verify that hydrogen embrittlement has not occurred during plating processes. When manufactured parts are to be tested, test fixtures specific to the individual part are designed and produced on our premises. The sharp notched tensile specimens used in this testing can be purchased from CMTL, subject to your plating process and then returned to us for testing. Stress Rupture The stress rupture life of notched specimens evaluates the ability of materials to deform locally without cracking under stress conditions by redistributing stresses around a stress concentrator. Testing can be performed at temperatures up to 2,000慚 and at any specified load. Sample Preparation Our on-site machine shop with over 25 years laboratory experience means that samples can be quickly and accurately prepared.