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Stress analysis of shrink-fitted pin-pin hole connections via Finite Element Method

Ozben T., Yardimeden A., Cakir O.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 25, nr 1

45-48

EN

Purpose: FEA analyses are frequently faced with modeling situations where field surface and changing contact cannot be assumed ignored. Design/methodology/approach: The effect of stress in machine elements due to friction between working machine parts has to be considered for analyzing the machine component with ANSYS software package. The interaction between the hole surface and pin was modeled with contact elements. In this study, examination of stress in pin-pin hole connections was carried out by using ANSYS program. Findings: The connection in pin-pin hole plates occurs between surface of pin hole in plate and side surfaces of pin. Stresses in contact surface of selected machine elements were investigated. Three different materials such as steel, aluminium and structure steel were analyzed under three different rates of cylindrical plate radius r and length of hexagonal pin 2h (r/h = 2.5, 5 and 7.5). Stress analysis was carried out in x, y and z axises. Research limitations/implications: Among the stress forms, in general, the maximum stress for all the three types of materials examined here was found to be occurring as the von Mises stress. Originality/value: The comparison of the maximum normal stress, maximum shear stress and von Misses stress were determined.

2

Selection of cutting fluids in machining processes

Cakir O., Yardimeden A., Ozben T., Kilickap E.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 25, nr 2

99-102

EN

Purpose: During machining operation, friction between workpiece-cutting tool and cutting tool-chip interfaces result high temperature on cutting tool. The effect of this generated heat affects shorter tool life, higher surface roughness and lowers the dimensional sensitiveness of work material. This result is more important when machining of difficult-to-cut materials, due to occurrence of higher heat. Design/methodology/approach: Different methods have been reported to protect cutting tool from the generated heat during machining operations. The selection of coated cutting tools are an expensive alternative and generally it is a suitable approach for machining some materials such as titanium alloys, heat resistance alloys etc. Another alternative is to apply cutting fluids in machining operation. They are used to provide lubrication and cooling effects between cutting tool and workpiece and cutting tool and chip during machining operation. Hence the influence of generated heat on cutting tool would be prevented. Findings: As a result, important benefits would be achieved such longer tool life, easy chip flow and higher machining quality in the machining processes. The selection of cutting fluids should be carefully carried out to obtain optimum result in machining processes. Various factors are affecting the selection of cutting fluid type in machining operation such as type of workpiece materials, cutting tool material and the method of machining processes. Research limitations/implications: In this study, the selection of cutting fluids for machining processes was examined. The effects of workpiece material, cutting tool and machining process type were determined in detail. Originality/value: In this study, the studies about cutting fluid application in machining processes have been evaluated. The selection criteria of cutting fluids have been examined. Suitable cutting fluids for various material machining processes have been determined according to cutting tool materials.

3

Photochemical machining of engineering materials

Cakir O.

Archives of Materials Science

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2007

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Vol. 28, nr 1-4

15-19

EN

Photochemical machining (PCM) is one of the important nontraditional machining processes in which photographic and chemical etching techniques are employed. The workpiece material is shaped by using a strong chemical solution to dissolve surface of the workpiece that was selectively exposed to machine areas using a photographic technique. The application of photochemical machining has increased extensively in the electronics, precision engineering, medical and decorative industries as well as in the microcomponentproduction industry. The present study is aimed to provide information on the application of PCM. The selection of etching parameters such as etchants for engineering materials, chemical additives into main etchants and etching temperature on the different machining outputs will be discussed. Also, the influences of environmental legislations on the machining process are examined and the future directions are considered.