How to Prevent Head Cracking in Stainless Steel Long Screws？

Release time：2020-01-16 18:44 Browse：

1. Use Cold Heading-Grade Stainless Steel

Select stainless steels like 304HC, 302HQ, or 316L, which are specially designed for cold forming. These materials contain higher nickel content and offer better plasticity, reducing the risk of cracking during forming.

2. Apply Proper Cold Heading Process

For long screws, use multi-station cold heading machines to form the screw head in multiple stages. This avoids excessive deformation and stress concentration that can cause cracking.
Control the pressing force and speed to prevent internal metal fiber rupture.

3. Intermediate Annealing Treatment

Apply intermediate annealing to the stainless steel wire before forming. This helps to restore ductility and reduce the risk of cracking caused by work hardening.

4. Use Quality Lubrication and Mold Surface Treatment

Ensure the mold surface is polished and apply high-performance cold heading oil to reduce friction and heat. This helps protect the screw surface and prevent micro-cracks.

5. Optimize Head Design

Avoid deep grooves or sharp corners in the screw head. Design with smooth transitions and thicker fillets to better distribute stress and reduce the likelihood of cracking during forming.