Microstructure and mechanical properties of laser cladding repair of AISI 4340 steel

Abstract

Laser cladding (LC) was used to investigate the repair of high strength steel in aircraft applications, such as landing gears. This paper reports on the microstructure and microhardness properties of the deposited AISI 4340 clad layer on AISI 4340 steel substrate. Microhardness results showed the clad layer was 30-40% harder than the base material. Stress relieving the clad allowed the clad and HAZ areas to soften 10% below the base material. High dilution provided a favorable result on the hardness at the interface.