- freely available
Metals 2014, 4(4), 586-596; https://doi.org/10.3390/met4040586
2. Experimental Section
3. Results and Discussion
3.3. Tensile Properties
|Sample||Microhardness (HV)||Ultimate tensile stress (MPa)||Total elongation (%)|
|473 K-4 P||162.9||333.2||24.7|
|473 K-16 P||201.2||583.4||37.9|
|673 K-4 P||150.9||365.5||22.5|
|673 K-16 P||168.6||461.1||26.9|
- Multi-pass ECAP processing, compared with cold drawing, improves grain refinement effect of the Conformed Cu-0.2wt%Mg alloy. More passes of ECAP leads to finer grains, and the grain size of the 16-pass sample ECAPed at 473 K is about 200 nm.
- Compared with the as-achieved sample in Conform state, the ones after multi-pass ECAP exhibit much higher strength with adequate ductility. The ECAPed samples for 16 passes have much higher strength and better ductility than those for less passes.
- With increasing the ECAP pass, hardness and strengthen of the ECAPed samples increased obviously but the conductivity decreased gradually. However, the conductivity of the Cu-0.2wt%Mg alloy after Conform plus ECAP is still much higher than that of the current Cu-0.4wt%Mg product processed by Conform plus cold drawing.
- Conform plus ECAP provides a simple and effective procedure to obtain high strength and good conductivity Cu-Mg alloy, in comparison with current Conform plus cold drawing. After Conform plus ECAP for 16 passes at 473 K, Cu-0.2wt%Mg alloy exhibits superior tensile strength (583.4 MPa), adequate total elongation (37.9%), good conductivity (84.5% IACS), and high hardness (201.2 HV).
Conflicts of Interest
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