This paper presents an analytical approach to predict the machining force, temperature and residual stress under minimum quantity lubrication (MQL) condition. Both the lubrication and cooling effects are considered to change the tribological and thermal properties in the modified Oxleys model, which is capable to predict the cutting force and temperature in MQL machining directly from cutting conditions. The machining-induced residual stress is predicted by modified McDowell hybrid algorithm. The predicted cutting forces and residual stresses are verified by orthogonal cutting tests for C45 steel and TC4 alloy steel.

Hardened AISI 1045 steel implemented in machine tool spindle was previously ground using grinding operation. This research aims to address the feasibility of hard turning AISI 1045 using PCBN tool with chip breaker under dry condition. Chip morphology, cutting force and temperature were measured, analyzed and correlated with machining parameters. Experimental results demonstrate that serrated chips are generated at high speeds, high feed rate is an assistant to promote serrated chips, and chip breaker can help break chip into acceptable lengths. Cutting forces were characterized with periodic fluctuation along three directions as chips are serrated. Temperature at machined zone can reach as high as 1200°C, which indicates that adiabatic shear bands can be successfully achieved during the machining of hardened AISI 1045 steel without applying lubricants.

In this paper, the cell potential method is used to determine the average activity coefficients of the NaBr–Na2SO4–H2O ternary system at 318.15 K. The ion-selective electrode and electrolyte solution are used to form a liquid-free battery. The ionic strength in the mixed solution is in the range 0.01–1.0 mol·kg–1 with different ionic strength fractions of Na2SO4, that is, y b = (0, 0.2, 0.4, 0.6, and 0.8). First, in a single salt solution, the response curve of Nernst can be obtained according to the Nernst equation. The standard cell potential E 0 = 251.03, electrode response slope k = 27.124, and linear correlation coefficient R 2 = 0.9998 are obtained in this work. In the same way, the average activity coefficients of NaBr in mixed electrolyte solution at 318.15 K were also determined by using the Nernst equation. Finally, the mixed ion interaction parameters θBr, SO4 and φNa, Br, SO4 of Pitzer equations can be fitted by the multilinear regression method combined with the average activity coefficients of mixed salt solution. In addition, the osmotic coefficients, water activity, excess Gibbs free energy, and activity coefficient of Na2SO4 can also be calculated using Pitzer equations based on the fitted θBr, SO4 and φNa, Br, SO4.

Hard turning has been recognized as a substitute for abrasive-based processes not only due to its flexibility, economic benefit and environmental consciousness, but also its determinate surface integrity (surface roughness, micro hardness and residual stress), which is superior and more consistent than ground surfaces. Residual stress is of considerable industrial importance because they can affect failure by fatigue, creep or cracking. It is believed that compressive residual stresses are more favorable for fatigue life than tensile residual stresses. Hard turning generally generates compressive residual stress, which is the dominant role in determining both the variance and average value of fatigue life. This paper focus on the published data, especially C.R.Liu’s research, which address the residual stresses by hard turning in terms of experimental approaches， theoretical modeling，numerical simulation by Finite Element Analysis (FEA) and the correlation with its fatigue life and performance. The potential trends and key technologies for residual stresses are predicated and discussed so as to capture the most effective approach to investigate residual stress by hard turning.

The resistance of rubber cutting can be divided into two aspects, the friction during cutting and the strength of the rubber. The strengths of rubber vary not only according to their molecular structure and detailed formulation, but also according to the deformation property. In order to obtain the mechanism of rubber cutting and correctly evaluate the influence of the cutting rate and the cutter's sharpness on the cutting resistance, a test apparatus is designed and an experimental method based on the fracture energy theory is investigated through cutting rubber such as Ethylene-Propylene-Diene Monomer (EPDM) using a sharp cutter. Through the analysis to the force of rubber cutting process, it's found the rubber cutting can be divided into several periods; through the analysis to the cutting force with different cutting rate, it's found that there is viscoelasitc effect when the rubber is cut with low speed; through the analysis to the cutting force with different cutter's bevel angles, it's found the cutting forces increase greatly with the increase of cutter's bevel angle. This work originally investigated the force of rubber cutting process, and the experiment result is very helpful to understand the mechanism of rubber cutting and to select appropriate cutting rate and cutter's geometry. And the study method and the mechanism of rubber cutting can be applied to other viscoelastic materials' cutting process.