Test Background
The properties of metal materials will undergo serious changes under low temperature conditions. The lower the temperature, the higher the strength of metal materials, but the plasticity will become worse, resulting in a phenomenon from toughness to brittleness. Therefore, studying the low-temperature properties of materials is of vital significance for the selection, failure analysis and safety assessment of materials working in low-temperature environments.
The low-temperature tensile test of metal materials refers to the metal tensile properties of the sample in the range of -196 ℃ to <10 ℃, and measures the maximum destructive force, tensile strength, yield strength, elongation, shrinkage and other indicators of the material.
Zhongke Testing and Reliability Experiment Center has the capabilities of environmental testing and reliability performance testing of various metal materials, and provides professional low-temperature tensile testing services for metal materials.
Scope of tests
Metal materials are usually divided into ferrous metals, non-ferrous metals and special metal materials.
1. Ferrous metals: iron, chromium, manganese and their alloys, etc.
2. Non-ferrous metals: divided into light metals, heavy metals, precious metals, semi-metals, rare metals and rare earth metals.
3. Special metals: amorphous metal materials obtained through rapid condensation process, as well as quasicrystalline, microcrystalline, nanocrystalline metal materials, etc.
Test method
1. The test system uses tensile force to stretch the sample, usually until it breaks, to measure one or several mechanical properties. The test is carried out at temperatures between -196°C and <10°C, that is, higher than the specified room temperature.
2. The low temperature test includes two test rate control methods.
Method A is based on strain rate (including beam displacement rate) and a narrow relative error (±20%).
Method A aims to reduce the change in test rate when measuring strain rate sensitive parameters and reduce the measurement uncertainty of test results.
Method B is based on traditional strain rate ranges and relative errors.
Test standard:
GB/T 228.3-2019 Metallic materials - Tensile testing Part 3: Low temperature test method
ISO 6892-3: 2015 Metallic materials - Tensile testing Part 3: Low temperature test method
BS ISO 6892-3: 2015 Metallic materials - Tensile testing Part 3: Low temperature test methods
