Preparation of Cu/Invar composites by powder metallurgy

Abstract

An orthogonal experiment scheme was employed to study the influences of forming pressure, sintering temperature and holding time and Cu content on microstructure, hardness and electrical resistivity of the Cu/Invar composites prepared by the powder metallurgy (PM) technique. The interdiffusion of the Fe, Ni and Cu atoms of the composites during sintering was also investigated. The results show that the Invar alloy is distributed continuously in the composites, when the Cu content is 30 wt-% and below; when the Cu content is 40 wt-% and above, a continuous net structure of Cu forms. Properties, especially the electrical and thermal conductivities, depend on the relative density and atom interdiffusion of the Cu/Invar composites. Taking the electrical resistivity of the composites as index, the optimum processing parameters are: forming pressure of 600 MPa, sintering temperature of 1000uC, holding time of 60 min and Cu content of 50 wt-%.

WEDM of Cu/WC/SiC composites: development and machining parameters using artificial immune system

“…The MLRM equation for samples 1 and 2 are given in Equations (8) and (9). The value of surface roughness obtained using MLRM equation both before and after implementation of AIS algorithm is compared with experimental value along with their absolute percentage error (APE) for samples 1 and 2 MMCs shown in Figures 6 and 7.…”

“…In the present work, reinforced particulates WC/SiC was mixed with Cu powder to improve the SiC/Cu interface. The reason for selecting tungsten carbides material is that WC has good adhesion with Cu and can prevent Cu from reacting with SiC [7,8]. The physical and mechanical properties of Cu composites were studied in the present paper.…”

Al/stainless-invar composites with tailored anisotropy for thermal management in light weight electronic packaging

“…The preparation of metallic composites with invar as second phase has been investigated for Cu matrix composites [24] but never for Al matrix composites. The only feasible route for preparing near-net shape plates of Al-matrix composite reinforced with a honeycomb structure is by infiltrating the honeycomb with liquid Al alloy using a technique such as squeeze casting.…”

Synthesis of Invar 36 type alloys from elemental and prealloyed powders by mechanical alloying

“…The mechanical alloying followed by SPS (spark plasma sintering) technique was used to obtain both Invar compacts and composite compacts of the Invar\Cu type. The Cu addition has a negative effect on the coefficient of thermal expansion [11,12]. It was proved that the introduction of nanocrystalline germs has positive effects on mechanical alloying process [13].…”