Hydrogen embrittlement risk: 1. Under normal circumstan […]
Hydrogen embrittlement risk:
1. Under normal circumstances, products with hardness >32HRC have the risk of hydrogen embrittlement. Therefore, all products with a grade above 10.9 (including grade 10.9) and products that have been carburized and heat treated (self-tapping screws) will be exposed to hydrogen embrittlement.
2. Hydrogen embrittlement means that when the product is electroplated, H+ enters the inside of the metal to form bubbles, which causes the screws to be used on the spot, but delayed fracture occurs within 24 hours.
3. the product with hydrogen embrittlement risk within 4 hours after plating, need to be sent to the hydrogen furnace, stored at 200 degrees Celsius for about 8 hours; this is called dehydrogenation.
4. hydrogen embrittlement treatment can greatly reduce the risk of hydrogen embrittlement, but can not be completely avoided, so in the case of the need to ensure 100% no risk of hydrogen embrittlement, the use of electroplating products is strictly prohibited; and the use of Dacromet, sandblasting and other surface treatment processes .
Fastener performance and processing direction:
1. High strength while ensuring toughness;
2. the same size can make the weight lighter;
3. the mechanical strength can be guaranteed to make the volume smaller;
4. the strength of the guarantee can strengthen the toughness;
5. The anti-corrosion ability can be enhanced under the condition that the appearance is satisfied;
6. Improvement in accuracy limit.