Mechanical strength

Strength

We have delivered fasteners with a strength exceeding class 15.9 for applications where down sizing, clamping force and strength are critical. In our product range we offer stainless fasteners ranging from strength class 8.8 to 16.9. Despite the high strength our unique materials offers a unique combination of ultra high strength and good ductility. Bumax Stainless steel fastners are resistant against hydrogen embrittlement.

High strength fasteners offers:

possibility to downsize the fastener or reduce the amount of fasteners with maintained clamp load
weight saving
compact design and smaller screw joints
a fasteners that are able to withstand higher static or dynamic stresses
higher safety factor
higher resistance against relaxation

Mechanical properties

in as delivered condition for screws and bolts

Grade	Dimension	Strength class	Tensile strength Rm, min (MPa)	Yield strength Rp0.2, min (MPa)	Elongation, min (mm)
BUMAX 88	M3-M36	88	800	640	0.3 d
BUMAX 109	M3-M20	109	1000	900	0.2 d
BUMAX Nitro	up to M42	109, 129	1000, 1200	900, 1080	0.2 d
BUMAX SA	up to M42	88, 109	800, 1000	640, 900	0.2 d
BUMAX LDX	up to M42	88, 109, 129	800, 1000, 1200	640, 900, 1080	0.3 d
BUMAX DX	up to M42	88, 109, 129	800, 1000, 1200	640, 900, 1080	0.3 d
BUMAX SDX	up to M42	88, 109, 129	800, 1000, 1200	640, 900, 1080	0.3 d
BUMAX HDX	up to M8	88, 109, 129	800, 1000, 1200	640, 900, 1080	0.3 d
BUMAX Ultra¹	up to M16	159, 169	1500, 1600	1350, 1440	0.2 d

The table should be used as a guide only of what is possible to achive in regards of mechanical properties and dimension for Bumax grades. Alteration might occur depending on design and dimension. Contact Bumax sales representative for more information.

1) Bumax Ultra is a grade that is tailor made to solve customer needs in regards of strength, ductility, fatigue and wear resistance. Values in the table are typical strength classes, but even higher strength can be achived on some designs and dimensions, up to tensile strength levels of approximatly 2500 MPa.