MITSUBISHI MATERIALSCopper & Copper Alloy Business

MITSUBISHI MATERIALSCopper & Copper Alloy Business


Products information

MZC1High conductivity high heat-resistant copper alloy

Standard No.
C18140 (Temper:1/2H, H), C18141 (Temper:SH)

Electrical conductivity , Strength and Stress relaxation resistance are high.
It is used for Moving contact for relays due to its high Electrical conductivity , Strength and Fatigue resistance.

Positioning of Alloy

MZC 1 is a chromium · zirconium type copper alloy, and is a high strength · highly conductive type copper alloy which achieves both tensile strength of 600 MPa and conductivity of 80% IACS. As an industrial material, it is regarded as one of the copper alloy systems in a region which is closest to the ideal region. Even with its heat resistance, it has excellent characteristics and thus is suitably used under the harsh environments.

Main features

  1. Highest balance between conductivity and strength among copper alloys
  2. Excellent heat resistance and stress relaxation resistance characteristics
  3. Contributing to downsizing of electronic parts, lower heat generation, and higher reliability
  4. Possible to process reflow-Sn plating with excellent surface quality and whisker resistance

Main application

Automotive terminal, Moving conntact for relay, consumer terminal, PV terminal, press-fit terminal
fuse, socket, EV, terminals for HV battery, breaker, electrical and electronic parts with heat generation due to miniaturization, and the like

Chemical composition

(Weight %)

Cr Zr Si Cu
0.25 0.1 0.02 Rem.
* Including inevitable impurities and trace additive elements

Physical properties

Property Representative Value
Specific Gravity
Coefficient of Thermal Expansion
(×10-6/K : 293~573 K)
Thermal Conductivity
(W/(m・K) : 293 K)
H;316 SH;287
Volume Resistivity
(µΩm : 293 K)
H;0.021 SH;0.023
Electrical Conductivity
(%IACS : 293 K)
H;82 SH;74
Modulus of Elasticity
(kN/mm: 293 K)

Mechanical properties (Actual example: LD direction)

The mechanical properties of MZC1 are as follows.

  Temper Typical Value
1/2H H SH 1/2H
Tensile Strength
500~600 555~655 575~725 538 598 632
0.2% Yield Strength
502 567 611
6以上 3以上 2以上 16 14 13
Elastic Limit*1
_ _ _ (471) (528) (559)
Vickers Hardness*2
(130~190) (160~220) (170以上) (164) (181) (202)
*1 sampling direction is T.D..
*1,*2 reference value

Stress relaxation resistance

MZC 1 also exhibits excellent stress relaxation resistance characteristics as compared with beryllium copper. Excellent properties can be exhibited in the stress relaxation resistance characteristics at 200°C.

Exposure temperature: 200℃
Sampling direction: Parallel to the rolling direction
Bending stress: 80% of 0.2% yield strength

Bending workability

Temper Sampling Direction Bending Inside Radius (mm) R Evaluation R/t
(to the rolling direction) 0.0 0.1 0.125 0.15 0.2 0.25 0.4 0.6 0.8 1.0

:(Good way)
:(Bad way)

:(Good way)
:(Bad way)
Method of evaluation: ◎Good (Acceptance)、○Minor rough surface (Acceptance)、△Major rough surface (Acceptance)、▲Minor crack (Rejection)、×Major crack (Rejection)

Fatigue Property

MZC 1 has almost the same fatigue characteristics as those of beryllium copper. Of course, MZC 1 does not contain hazardous substances, and thus is recommend especially for people thinking about substitution from beryllium copper.


Rolled product Sales Dept.