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Role of Si on machined surfaces of Al-based automotive alloys under varying machining parameters

Razin Ahmed Asif, Ahammed Dewan Salsabil, Nur Maglub Al, Kaiser Mohammad Salim

Journal of Mechanical and Energy Engineering

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2022

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Vol. 6, No 1

43--52

EN

A morphological change due to Si contend into Al-based automotive alloys has been conducted on the characterization of machined surfaces in terms of roughness, temperature, chips formation as well as microstructure evaluation under different machining conditions. For this experiment, a shaper machine with HSS single point V-shaped cutting tool is used at different cutting speeds and depths of cut. The experimental results show that the surface roughness of the alloys decreases with the cutting speed and depth of cut but it is more prominent in the case of the cutting speed. This is because of a high cutting speed, which is more associated with the higher temperature and softening the work material leading to better surface finish. Higher Si added alloys also exhibit a better surface finish because the sample content is different fine and hard intermetallic due to ageing treatment, which also makes the alloys more brittle. For brittle and higher hardness, it produces a higher temperature during machining. During machining, relatively curly and short chips are formed by the high Si added alloy because of its low elongation properties. The fracture surfaces of higher Si added alloy display more crack propagation obtained by plate-like Si rich intermetallic.

2

Role of magnesium and minor zirconium on the wear behavior of 5XXX series aluminum alloys under different environments

Kaiser Mohammad Salim, Matin Mohammad Abdul, Shorowordi Kazi Mohammad

Journal of Mechanical and Energy Engineering

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2020

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Vol. 4, No 3

209--219

EN

The tribological performance of 5xxx series aluminum alloys with ternary zirconium is evaluated at ambient conditions under dry, wet and saline environment. The experiment has been done using a Pin-on-Disk apparatus under an applied load of 20N. The sliding distances varies ranging from 116m-2772m at a sliding velocity of 0.385 ms-1. The results show that presence of Mg and Zr into this alloy helps to increase their strength and wear resistance under dry sliding condition. But they significantly suffer under wet and corrosive environment due to formation of β-phase Al3Mg2, to slip bands and grain boundaries which may lead to and stress-corrosion cracking. The variation of friction coefficient is observed in wet and corrosive environment due to the formation of oxidation film, lubrication, and corrosion action in solution. The SEM analysis shows that brittle Al3Mg2 phase initiate the fracture surface for Al-Mg alloy and Zr addition accelerate the brittleness of the alloy owing the fine precipitates of Al3Zr.

3

Effect of cutting parameters and machining environments on the chips characteristics and surface quality of commercial high-conductive materials

Kaiser Mohammad Salim, Rahman Khandaker Tawshif, Ahmed Sheikh Reaz

Journal of Mechanical and Energy Engineering

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2020

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Vol. 4, No 4

325--334

EN

The present paper is on the physical and mechanical characterization of machined chips of commercially available highly conductive materials, namely aluminium and copper under different machining environments. More specifically, geometry and hardness of chips as well as the chips removal effect on the machined surfaces are investigated in a quantitative fashion as a function of machining fluid and cutting parameter. The machining is carried out using a horizontal shaper machine with a V-shaped HSS tool under three different machining fluids, where the feed rate is kept constant, while the cutting speed and depth of cut are varied. Results show that chips attain the lower hardness in dry machining conditions than those of under kerosene and soluble oil as a phenomenon alike to hot rolling. Discontinuous chips are formed at low depth of cut for Al and higher depth of cut for Cu in dry condition. Cutting fluid offer improved surface quality through less friction and built up edge formation. Cu generates more heat than Al since copper is harder than aluminum and cutting speed is more effective than depth of cut.