Effect of Cu content in Cu–Ti–B4C system on fabricating TiC/TiB2 particulates locally reinforced steel matrix composites

The austenite manganese steel–matrix composites locally reinforced with in situ TiC/TiB2 particulates were successfully fabricated using self-propagating high-temperature synthesis (SHS) reactions in a Cu–Ti–B4C system and the effect of the Cu content during casting has been investigated. The local reinforcing regions in the steel matrix composites mainly consist of TiC, TiB2, Cu and austenite, without any intermediate phases. With the increase in the Cu content, the size of the ceramic particulates in the local reinforcing regions decreases, the interface bonding between reinforcing region and matrix becomes poor and the macro-pores and blowholes in the local reinforcing regions become fewer. Moreover, with the increase in the Cu content, the hardness value decreases monotonically, while the wear resistance of the reinforced region increases first then decreases.