Products + Tools

The new BUMAX® Ultra range of unique precipitation hardened stainless steel fasteners from BUMAX boasts tensile strengths exceeding 1,700 MPa and are specifically designed for applications where ultra-high strength combined with high ductility is required in the final product. 

BUMAX Ultra achieves its super high strength from strain hardening and precipitation hardening. After precipitation hardening the tensile strength increases significantly. BUMAX Ultra has a corrosion resistance comparable to 316L (A4) and can be used at service temperatures between -50°C to 400°C with retained mechanical properties.

Despite being manufactured from stainless steel, the bolts are frequently used to replace high strength carbon steel fasteners in critical applications – where the requirements on strength and ductility are extreme. BUMAX Ultra has a coefficient of thermal expansion similar to that of carbon steel, which gives it design advantages when compared with austenitic stainless steels. The very high strength to weight ratio in combination with its good formability and ductility make it a very attractive fastener alternative to other lightweight materials such as titanium.

All fasteners in the BUMAX Ultra range are custom-made to meet the requirements of individual applications and can be delivered with different mechanical properties, with a tensile strength exceeding 1,700 MPa. BUMAX Ultra is an advanced engineering grade and close technical support is provided by BUMAX AB for customer projects in order to develop the desired end solution. Current applications for BUMAX Ultra include security lock systems, aerospace systems, high pressure applications and pump and valve systems.

BUMAX Ultra is made in BUMAX’s factory in Åshammar, Sweden, and is manufactured using Nobel Prize winning Quasi-Crystalline Precipitate technology.