γ－TiAlの超音波砥粒加工

抄録

The paper initially reviews γ-TiAl alloy. Experimental research is presented on the production of 3mm diameter holes in Ti-45Al-2Mn-2Nb+0.8%vol TiB₂ using ultrasonic machining techniques. This entailed the use of a 20kHz piezoelectric transducer /250W generator, with both solid and hollow polycrystalline diamond (PCD) tools, operating in a boron carbide slurry. Fractional factorial Taguchi analysis was employed to evaluate 5 operating factors each at 2 levels, using an L8 orthogonal array with extensive replication. The data presented includes main effects plots for material removal rate (MRR) and tool wear rate (TWR), together with sample hole entry/exit photographs and corresponding workpiece surface roughness and surface integrity information (cross sectional mic rographs, microhardness depth profile plots and surface residual stress data).