PM Non Ferrous: Self-lubricating Copper Composites for Vacuum and Space

• Published in: European Congress and Exhibition on Powder Metallurgy. European PM Conference Proceedings Vol. 4; p. 1
• Main Authors: Merstallinger, A, Neubauer, E, Calard, V, Gaillard, L, Pambaguian, L
• Format: Conference Proceeding
• Language: English
• Published: Shrewsbury The European Powder Metallurgy Association 01.01.2004

Self-lubricating Cu-MMCs for use in mechanical systems under vacuum or space are not commercially available till now, and usually, published papers on frictional behaviour of such Cu-MMCs report friction coefficients higher than 0,3. In order to improve the performances of the promising Cu-MMCs not only in space applications but also in vacuum systems on ground, a PM-process was optimised to produce high quality composites with solid lubricants by avoiding reaction between copper and MoS^sub 2^ particulates. Two routes were followed: a hot compaction of "conventionally mixed" powders and a hot compaction of "coated particles", i.e. the particles were coated with copper before compaction. Cu-MMCs with two kinds of lubricant particles (MoS^sub 2^ and short carbon fibres) and contents up to 40v% were also produced. Compression tests at RT revealed that strength and modulus are higher for the Cu- MMCs based on coated particles. Pin-On-Disc tests confirmed friction coefficients under vacuum less than 0,1 at RT, and less than 0,2 at 300°C. [PUBLICATION ABSTRACT]