Proper use of Beryllium Copper

(2) Stamping

Materials of pressing dies for Beryllium Copper Alloys may be the same as those for other Copper Alloys. However, pressing oil must be chosen carefully. In particular, oil of high chlorine or sulfur content should be avoided because such oil may cause discoloration, or may affect plating or soldering. The normal die materials can also be used for mill-harden materials. However, super-hard alloys are often used when a large number of parts are punched, or when the accuracy of punching or the life of the die must be improved. See Tables 4 to 6 for bend radii (R) for bending. The pressing of Alloy 25 must be performed before age-hardening treatment. These materials are very difficult to bend after age-hardening treatment. Although they can be punched into simple shaped products, the life of dies are shortened. Since mill-harden Alloy 25, and alloys 11, 10, and 7 after pressing can be used as parts as they are, age-hardening treatment is not required.

Fig. 3 Relative Formability R/t

Table1 Relative Formability of High Strength Material(90° bending)

Alloy	Type	Temper	R/t		Typical R/t in thickness 0.15mm
			Long.	Trans.	Long.	Trans.
25	AH	O	0.0	0.0	0.0	0.0
		1/4H	1.0	2.0	0.0	0.0
		1/2H	3.0	4.5	0.0	0.0
		H	-	-	0.0	1.7
	MH	OM	0.8	2.0	0.0	0.6
		1/4HM	1.0	3.0	0.3	1.0
		1/2HM	2.0	4.0	0.6	2.7
		HM	3.0	6.0	1.0	4.0
		XHM	4.0	-	3.0	-
		XHMS	6.0	-	4.0	-
	MH TypeB	OMB	0.8	0.8	0.0	0.0
		1/4HMB	1.0	1.0	0.0	0.0
		1/2HMB	1.3	1.3	0.0	0.0
		HMB	2.5	2.5	0.6	0.6
		XHMB	3.4	3.8	1.7	1.7
		XHMSB	4.1	6.0	3.5	6.0
	MH TypeS	HM-TypeS	1.5	1.5	0.0	0.0
		XHM-TypeS	2.5	2.5	1.0	1.0

Table2 Relative Formability of High conductive Material(90° bending)

Alloy	Temper	R/t		Typical R/t in thickness 0.15mm
		Long.	Trans.	Long.	Trans.
8	HT	1.0	1.0	0.0	0.0
11	HT	2.0	2.0	0.0	0.0

Table3 Relative Formability of Midrange Material(90° bending)

Alloy	Temper	R/t		Typical R/t in thickness 0.15mm
		Long.	Trans.	Long.	Trans.
7	1/2HT	0.0	0.0	0.0	0.0
	HT	1.5	1.5	0.0	0.0
	EHT	2.0	1.5	0.3	0.0