The mechanical properties of stainless steel storage tanks are very important, which are related to the performance and quality of deformation, stamping, cutting and other processing using stainless steel as raw materials, so mechanical properties testing is required. There are two main types of mechanical properties testing methods, one is tensile test and the other is hardness test.
The tensile test is to make a stainless steel storage tank into a sample, pull the sample to break on a tensile testing machine, and then measure one or more mechanical properties, usually measuring tensile strength, yield strength, elongation after fracture and cross section. Shrinkage.
The hardness test is to slowly press a hard indenter into the surface of the sample according to the specified conditions, and then test the depth or size of the indentation to determine the hardness of the storage tank. The hardness test is a simple and easy-to-implement method in the mechanical property test of stainless steel storage tanks. The hardness test is non-destructive, and there is an approximate conversion relationship between the tank hardness value and the tensile strength value.
Since the tensile test is inconvenient to test, and the conversion from hardness to strength is convenient, more and more people only test the hardness of the storage tank and less test its strength. Due to the continuous progress and innovation of the manufacturing technology of hardness testers, some storage tanks that could not directly test the hardness before are now possible to test the hardness directly. Therefore, there is a tendency for hardness testing to gradually replace tensile testing.
Most of the standards for stainless steel storage tanks specify both tensile tests and hardness tests. For those tanks that are inconvenient for hardness testing, such as stainless steel tubing and wire, only tensile testing is specified. In the stainless steel standard, three hardness test methods of cloth, Luo and Wei are generally stipulated, and the hardness values of hb, hrb (or hrc) and hv are determined, and only one of the three hardness values can be measured.
