Effect of thermo-mechanical loading on machining induced residual stresses in ultrasonic vibration assisted turning of Ti6Al4V alloy

Abstract

The study of residual stresses induced during machining is of considerable importance due to their effect on fatigue life of machined components. The metallurgical changes occurred due to thermo-mechanical phenomenon in cutting process affects the distribution of residual stress in machined components. Ultrasonic vibration assisted turning (UVAT) is effective machining process for low thermal conductivity materials like Ti6Al4V alloy and improves the surface characteristics by reducing cutting force and cutting temperature. In this paper, experimental and finite element (FE) studies are conducted to study the circumferential and axial residual stress distribution in UVAT of Ti6Al4V alloy. FE model is developed to study the effect of vibrating parameter (ultrasonic power intensity) and cutting parameters (cutting speed, feed rate, and depth of cut) on the residual stress profiles of machined surface. The FE simulation results of cutting force and cutting temperature are validated with experimental results. The circumferential and axial surface residual stresses obtained from FE simulation are also compared with experimental results using X-ray diffraction method. The effect of thermo-mechanical loading on residual stress distribution is analyzed with respect to force components (cutting force and feed force) and cutting temperature. Finally, the effect of each cutting parameter on subsurface layer of machined component is analyzed.

On the correlation between processing parameters, plastic deformation, and mechanical property in hard machining of H13 steel

“…As the edge hone radius increases, the contact area between the edge hone and workpiece increases, as well as the deteriorated friction behavior, 31,36 which leads to higher cutting forces and cutting temperature in the shear deformation zones. 37,38 Since the plastic deformation results from a highly coupled thermal-mechanical load in the metal cutting process, 11,39 the observed large depth of plastic deformation using cutting tools with a large edge-hone radius can be reasonably expected.…”

“…Considering the ironing action, compressive residual stress is inclined to generate within the machined surface layer. 37 Furthermore, compressive residual stress benefits fatigue crack inhibition and ameliorates fracture toughness. Although the estimated lower fracture toughness is not always corresponding to a larger depth of plastic deformation, to a certain indicates that machining-induced plastic deformation is not the sole factor.…”

Performance evaluation of spot cooled vibration assisted turning for Ti6Al4V alloy

“…The lack of proper heat dissipation results in high heat accumulation causing tensile residual stresses in CT. Though compressive residual stresses are formed in VAT due to the presence of ultrasonic assistance, 52 the heat dissipation is not so effective as in case of VTSC and SCVAT, thereby reducing the magnitude of stresses. It is noteworthy that SCVAT performed better than VAT in terms of magnitude and CT in terms of nature of stress.…”

Atomic simulation of the effect of supersonic fine particle bombardment process parameters on the mechanical properties of polycrystalline γ-TiAl alloy

“…Previous research has primarily focused on investigating the impact of process parameters on residual stresses and mechanical properties. Specifically, these studies have examined the effects of cutting [4,5], annealing [6,7], milling [8], and grinding [9]. Through experimental studies, Wu and Matsumoto [10] discovered that the change in residual stress pattern is primarily related to the shear angle during chip formation.…”