LASER-MELT INJECTION OF B4C ON TITANIUM

This paper is description of some results obtained by injecting B4C powder into a laser-generated titanium melt pool. Between the boron carbide particles and the melted titanium, exothermic reactions take place. At relatively high beam energy inputs, these reactions cannot be properly controlled and the tracks are inhomogeneous and porous. Effective control of the processing parameters, however, results in uniform distribution of the boron carbide in a relatively soft matrix, with very good adhesion under optimum conditions. The adhesive effect is associated with a reduction in the free energy owing to the chemical reactions at the particle-matrix interface which contain TiC, titanium borides and free titanium. The matrix contains titanium, TiC, TiB and TiB2. © 1990.