Custom 450 (UNS S45000)

* Brief
Custom 450 (XM-25, UNS S45000) is a age-hardenable martensitic stainless steel that has very good corrosion resistance and moderate strength. Although the alloy has a yield strength higher than 689 MPa in the annealed condition, it is easily fabricated. A single-step aging treatment develops higher strength with good ductility and toughness. Because it has corrosion resistance similar to alloy 304 stainless and with much higher yield strength, Custom 450 has been used in applications where alloy 304 was not strong enough. It has also replaced alloy 410 stainless directly on a strength basis where alloy 410 had insufficient corrosion resistance.

* Specification

Rod, Bar, Wire, Forgings	Plate, Sheet, Strip	Pipe, Tube
ASTM A564, ASTM A705, ASTM A959	ASTM A693, AMS 5859, AMS 5863	AMS 5763, AMS 5773

* Chemical composition, %

C	Mn	Si	P	S	Cr	Ni	Mo	Cu	Fe
0.05	1.00	1.00	0.03	0.03	14.0~16.0	5.0~7.0	0.5~1.0	1.25~1.75	Bal

* Physical property

Density, g/cm3	Specific heat, J/g ℃	Thermal conductivity, W/m-k H900	Mean coefficient of thermal expansion, 75-200F	Modulus of elasticity, MPa
7.75	0.477	15	5.88*10-6	193-200*103

* Typical mechanical property (Solution annealed)

Tensile strength, MPa	Yield strength, MPa	Elongation, %	Hardness, Rc
979	814	13	28

* Feature
It has very good corrosion resistance and moderate strength. Although the alloy has a yield strength higher than 100 KSI (689 MPa) in the annealed condition, it is easily fabricated. A single-step aging treatment develops higher strength with good ductility and toughness.

* Application
1.Screens for the pulp and paper industry
2.Medical devices
3.Aircraft parts
4.Power generation applications
5.Chemical processing
6.Nuclear applications