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In this experimental study, tensile and fatigue properties of the Alumix 431 alloy (Al, Zn, Mg and Cu alloys) produced using the conventional press and sinter processes in different pressures and temperatures are investigated. The results clearly showed that the warm compacted specimens can reach the mechanical properties of the cold compacted ones under less pressure. In the fatigue tests it was observed that fracture started from large pores as shown in all scanning electron microscope (SEM) examinations and ductile fracture occurred. 85% of the 180 MPa/80°C and 77% of the 230 MPa/RT specimens fractured at the machined surface. Tensile and fatigue properties of warm compacted (180 MPa/80°C) and cold (230 MPa/RT) compacted specimens are almost equal at these same densities. This result indicates the economic benefit of warm compaction by the much lower applied compaction pressure

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In this work, the densification behaviour, sintering characteristics, hardness, strength, tensile and fatigue properties of the Alumix 431 alloy (Al, Zn, Mg and Cu alloy) produced using the conventional press and sinter process in different pressures and temperatures are investigated. For this purpose, specimens were produced under pressures between 300 and 500 MPa at 50 MPa intervals at room temperature (RT), and 80 C in the first step. In the second step, specimens were produced at the compaction pressure of 230 MPa under RT and 180 MPa with 80 C for tensile and fatigue testing which provided same densities. Specimens were sintered under five different sintering conditions. The dimensional change in warm compacted samples is lower than that of cold compacted samples. Tensile and fatigue properties of warm (180 MPa pressure) and cold (230 MPa pressure) compacted specimens are almost equal due to the same densities.Key words: Sintered aluminum, tensile and fatigue properties, mean stress sensitivity, cold and warm compaction, sintering conditions, mean stress sensitivity.

Bu makaleye şu şekilde atıfta bulunabilirsiniz(To cite to this article): Acar A.N., Ekşi A. K. ve Ekicibil A., "The physical properties of aluminium-7xxx series alloys produced by powder metallurgy method", Politeknik Dergisi, 21(2): 341-350, (2018).Erişim linki (To link to this article): http://dergipark.gov.tr/politeknik/archive DOI: 10.2339/politeknik.389588 Politeknik Dergisi, 2018;21(2):341-350 Journal of Polytechnic, 2018;21(2)

Cutting forces play a significant role in machining because they directly affect the mechanics of machining, the energy requirements, and the tool stability required. In this study, the cutting forces occurring during the turning of AISI 4340 material with 30 Rockwell C hardness scale have been analyzed both experimentally and numerically. Many types of research have been conducted via 2-D simulation using the finite element analysis method. In other words, in most studies, the workpiece was modeled as a flat specimen. Therefore, this paper presents a real 3-D turning simulation model using cylindrical specimens. The cutting forces were measured using a Kistler 9129AA model piezoelectric dynamometer. The ABAQUS/Explicit finite element method was used, and a model by Johnson and Cook was assigned as a material model in the numerical analysis. A new PVD AlTiN coated carbide insert was incorporated to prevent wear. Experimental results obtained from cutting tests were compared with numerical results to establish the accuracy of the FEM. It was observed that experimental and numerical results overlapped each other. Thus, this method can be used directly in the industry to reduce high processing costs.