CZ135 is a high tensile brass which is alloyed with aluminum, manganese and silicon etc. By alloying brass with strength-increasing elements, you get an alloy that is almost as hard as aluminum bronze, but considerably easier to process. The material also has good corrosion and wear resistance.

Chemical Composition

Elements Min (%) Max (%)
Cu 57.00 60.00
Pb 0.80
Sn 0.30
Fe 0.50
Al 1.00 2.00
Mn 1.50 3.50
Ni 0.20
Si 0.30 1.30
Total Others 0.50
Zn Remainder

Mechanical Properties according To BS2874 CZ135 (As Per Temper M)

Range (mm) From To UTS Min (N/mm2) UTS Max (N/mm2) PS Min (N/mm2) Elongation Min (%) Hardness Min Hardness Max
Round (Dia) 1.5 40 550 270 12
40 75 550 270 12
Hex (A/F) 3 40 550 270 12
40 70 550 270 12
Square (A/F) 3 40 550 270 12
40 60 550 270 12
Rectangle Thickness 3 40 550 270 12
Thickness 40 50 550 270 12

PHYSICAL PROPERTIES
Melting range 875–910 °C
Density 8.0 g/cm3
Electrical Conductivity 7-8 MS/m
Heat conductivity 60-70 W/(m*K)
Heat capacity 377 J/(kg*K)
Coefficient of thermal expansion 20 10-6/ K
Young’s modulus 95 GPa

FABRICATION PROPERTIES
Technique Suitability
Cold formed Poor
Hot worked Good
Machinability Rating 30%
Resistance to Corrosion Excellent
Suitability for Soldering Excellent