Influence of high temperature on surface hardness of AA7050 hybrid composites

In this work,aluminium alloy aa7050 used in manufacturing of main landing gear links was reinforced with boron carbide particles and silicon carbide particles fabricated through stir casting. the potassium fluotitanate was added as flux material to overcome the wetting problem. the composites were subjected to high temperature through electric discharge machining and its impact on surface hardness of composites was analysed. the pin on disc test was performed on the composites at a high load of 490n. the hardness of as cast,worn surface and electric discharge machined surface were compared. it was found that hardness of the composites exposed to high temperature was lower than as cast due to particle detachment. at high loads particles detached due to delamination wear. the worn surface hardness was higher than as cast composites due to presence of ferrous which was transferred from counter disc due to abrasion. © 2017,university of mohammed premier oujda morocco.