Surface Modification of A Cr–mo Steel Using Laser Surface Alloying with B₄C Powder Injection

Abstract

Specimens of an AISI4135H steel were traversed across a focused laser beam and superficially alloyed using a co-deposition technique involving B₄C powder injection. The metallurgical phases appearing at different depths in the laser surface alloyed steel have been identified using optical microscopy and SEM observations as well as X-ray diffraction analyses and Auger electron spectroscopy. A high hardness in the melted zone was generally obtained. Optimum process parameters including powder feedrate and specimen traverse rate have been determined to avoid porosity or cracks.