Characterisation of the wear properties of a single-aggregated cubic boron nitride grain during Ti–6Al–4V alloy grinding

Abstract

Single-grain grinding the Ti–6Al–4V alloys is performed to investigate the wear characteristics and material removal mechanism of aggregated cubic boron nitride (AcBN) grains fabricated by multiple monocrystalline cBN grains. An innovative approach entailing the tracking of grains and scratches by using the 3D reconstruction is proposed to investigate accurately the wear characteristics and material removal ability of such grains. Grain wear, which is affected by grinding wheel speed vs and undeformed chip thickness agmax, is characterised. The variations in grinding force and grinding force ratio, volumetric pile-up ratio and volumetric groove removal rate are also studied. Results show that the as-sintered AcBN grains have better self-sharpening ability, higher grinding ratio, and more stable grain wear rate than the McBN grains. In addition, the wear rate of AcBN grains is more sensible in determining the effect of vs compared with the use of agmax. The AcBN grains attained a higher wear volume (nearly thrice the value), a more stable wear rate and a more stable grinding force ratio when vs increases to 120 m/s as opposed to the other smaller vs values regardless of the agmax values.