Materials

The basic components of self-aligned bearings are balls, races, and bodies. The materials for these components are basically divided into two types: ferrous materials and non-ferrous materials. Materials are carefully selected and combined based on several requirements such as cost, safety and resistance, in accordance with operating condition. For particular applications, special treatments shall be additionally considered, such as heat treatment, surface treatment and others. The Table 3 shows materials characteristics and major applications.

Table 3 : Commonly used materials
Basic Classification	Types of Material	Typical Material Code		Characteristics	Major Applications
Ferrous Materials	Constructional Low Carbon Steel	S10C S45C	S15C S48C	Usually not hardening Suitable for general strength	Bodies for Rod End
	Constructional Alloy Steel	4340 SCM435H	4130	Good hardenability High toughness and strength	Bodies for 3 Piece Rod End
	Bearing Steel	SUJ2 52100	SUJ3	Possible to obtain high hardness by hardening Strong against rolling fatigue Good for anti-wear action	Balls for Rod End and Spherical bearing Races & balls for fracture type bearing (typical ball bearing material)
	Stainless Steel	440C		Possible to obtain high hardness (especially balls for PTFE lined bearings) Suitable for fractured type (races and balls)	Balls for Rod End and Spherical bearing
		410		A typical martensitic stainless steel	Races for Spherical bearing Sleeves
		17-4PH SUS630	15-5PH	High strength stainless steel High toughness	Bodies for 3 Piece Rod End Races for Spherical bearing Sleeves
		303		Excellent corrosion resistance Non heat treatable	Bodies for 2 Piece Rod End
	Heat Resisting Steel	A286 INCONEL®	STELLITE®	Good resistance to high temperature creep and corrosion	Bodies, races & balls for Rod End Bearing (aerospace applications)
Non-ferrous Materials	Aluminum Bronze (Al-Bz)	C62300	C64200	High strength copper alloy Good resistance to sea water Good for anti-wear action	Races for spherical bearing
	Beryllium Copper (Be-Cu)	C17200		High hardness possible by age-hardening (approx. 40HRC) Good for anti-wear action	Balls for Spherial bearing
	Aluminum Alloy	2024	7075	Light weight provides strength equal to steel	Sleeves Races & balls for spherical bearing
	Titanium Alloy	Ti-6Al-4V		Light weight High toughness and strength	Bodies for Rod End