After heat treatment, higher strength, better plasticity, better toughness, lower notch sensitivity and higher bending strength can be obtained, that is to say, the fastener can have better performance after heat treatment and avoid the occurrence of relaxation, thus maintaining good reliability and stability.
The heat treatment of fasteners can obviously improve the strength, especially when producing high-strength fasteners, heat treatment process is needed to improve the internal quality of fasteners. If the strength of fasteners wants to reach a higher level, we must first have advanced heat treatment technology and mature heat treatment technology control ability.
After heat treatment, the result of the fastener is to change the internal structure of the material and give the material some non-intuitive internal quality, thus greatly improving its mechanical properties, and the heat treatment process will hardly change the material and shape of the fastener itself.
After heat treatment, the appearance of fasteners rarely changes, so it is difficult to judge the improvement of fastener quality with naked eyes. In order to ensure the quality of heat treatment, production enterprises generally conduct random sampling inspection on the fasteners produced by special instruments to understand the specific situation of fasteners.
The mass production of fasteners determines that we can't control the quality of products after heat treatment to 100%, but can only test individual sampled products, so the test data obtained can only reflect the quality level of a fastener itself, but can't fully represent and reflect the quality of the whole fastener after heat treatment.
The heat treatment process control of fasteners is a better quality control method instead of inspection. For this reason, many fastener manufacturers have implemented comprehensive process management, and have also carried out ISO9000 series certification. By controlling the four factors of heat treatment, the heat treatment quality of fasteners is finally guaranteed.
