bedra69300

Silicon Brass

Characteristics：

bedra69300 is a high-performance, lead-free silicon brass alloy，its strength is comparable to stainless steel, and it is resistant to stress corrosion cracking and dezincification. It is an environmentally friendly material that fully complies with the RoHS and ELV directives, and is widely recognized as an ideal substitute for conventional lead-containing machining brass.

Typical applications:

It is widely used for faucet components, automotive parts, and electrical components, including faucet fittings and sprinkler heads, turbocharger bearings, relief valves, temperature sensors, insert nuts, 2- or 3-way valves, flare nuts, and terminals for air conditioners.

Standardization and composition

UNS	C69300
EN	CuZn21Si3P (CW724R)
JIS	/
GB	T68320 (HSi75-3)
Cu	73.0-77.0%
Si	2.7-3.4%
P	≤ 0.05-0.1%
Pb	0.005%
Others	0.4%
Zn	balance%

Physical properties①

Note①：The testing temperature is 20℃. Note②：The testing temperature range is 20℃ to 300℃.

Density	8.3 g/cm3
Melting point	880 ℃
Electrical conductivity	8 %IACS
Thermal conductivity	38 W/( m·K)
Coefficient of thermal expansion ②	18.7 10-6/K
Modulus of elasticity	104.8 GPa
Dezincification Depth (max.)	100 μm

Fabrication Properties

Note③：C36000 = 100%

Capacity for being cold worked	Poor
Capacity for being hot formed	Excellent
Brazing	Good
Resistance welding	Good
Machinability rating ③	85 %

Mechanical Properties

Temper	Diameter(mm)	Tensile Strength(MPa min.)	Yield Strength(MPa min.)	Elongation(% min.)	Hardness(HBW min.)
R500	6.0 ≤ Φ ≤ 80	500	max. 450	15	130
R600	10 ≤ Φ ≤ 40	600	300	12	150
R670	2.0 ≤ Φ ≤ 20	670	400	10	170

Dimension Tolerance and Delivery Form

Note④：The tolerances listed in the table are specified as all plus or all minus. When tolerances are specified as plus and minus (±), half the values given.

			Straight bar
Diameter (mm)	Tolerance④(mm)	Ovality (mm max.)	Length (mm max.)	Straightness (mm/m max.)
3.0 ≤ Φ ＜ 10	0.04	0.02	3600	0.5
10 ≤ Φ ＜ 16	0.05	0.025	3600	0.5
16 ≤ Φ ＜ 25	0.10	0.05	4000	0.8
25 ≤ Φ ＜ 35	0.12	0.06	4000	0.8
35 ≤ Φ ＜ 45	0.15	0.075	4000	1.0
45 ≤ Φ ＜ 55	0.20	0.10	4000	1.0
55 ≤ Φ ＜ 80	0.30	0.15	3000	1.5
80 ≤ Φ ＜ 120	3.0	1.50	1500	5.0