Interpreting the cross-section of the universal test machine from 3 points

Interpreting the cross-section of the universal test machine from 3 points

I've talked a lot beforeUniversal testing machineThe maintenance, repair and other operations are all about the overall operation. Today we provide you with the operation of the cross-section of the universal test machine, hoping to help you in your work.

1. Definition of cross-section shrinkage

One of the plasticity indicators of materials. When the material breaks under tensile force, the cross-section shrinks. The ratio of the area of ​​the cross-section shrinkage to the original area is called the cross-section shrinkage rate, represented by ψ or Z. Unit is %.

two.Universal testing machineThe relationship between cross-section shrinkage and elongation

Elongation and cross-section shrinkage represent the ability of the steel to undergo plastic deformation before breaking. The greater the elongation or the higher the cross-section shrinkage, the greater the plasticity of the steel. Steel has high plasticity, which not only facilitates various processing, but also ensures the safe use of steel in buildings. Because the plastic deformation of steel can adjust local peak stress and make it flatten, so as to avoid local damage to the building structure and the entire structural damage caused by it; before the plastic damage, steel has obvious deformation and a long deformation duration, which is convenient for people to discover and remediate.

3. Test of cross-section shrinkage rate of metal materials

1. Test subjects

The uncertainty of the cross-section shrinkage index of AlSi12Cu rod was evaluated.

2. Reference standards

JJF 1059-1999 Evaluation and representation of measurement uncertainty

JJG 139-1999 Testing procedures for tensile, pressure and universal testing machines

GB/T 228-2002 Room temperature tensile test method of metal materials

JJF 1103-2003Universal testing machineData acquisition system evaluation