Effect of Alloying Interlayer on Interfacial Bond Strength of CuW/CuCr Integral Materials

The effects of Fe alloying interlayers with different content on microstructures and mechanical properties of dissimilar CuW/CuCr joints prepared by sintering-infiltration method were studied. Microhardness (HV) and tensile tests were used to evaluate the mechanical properties of the resulting joints. Additionally, optical, scanning electron microscopy examinations and energy dispersive spectrometry elemental analyses were applied to determine the interfacial characteristics of CuW/CuCr integral materials. The results show element Fe in the alloying interlayers is mostly diffused to the Cu-W composite side, the Cu/W interphase has achieved the metallurgical bond, and the CuW/CuCr integrated material with Cu-5wt%Fe alloy interlayer exhibits higher interfacial bond strength. However, when the Fe content in the interlayers is above 5wt%, the W skeletons near the interface are dissolved and eroded by element Fe addition, the amount of eutectic phase is increased and the microhardness on copper matrix is decreased for the Cu-Cr alloy side near the interlayer, and the interfacial strength of CuW/CuCr integrated materials is also decreased.