AMA, Agricultural Mechanization in Asia, Africa and Latin America (AMA) (issn: 00845841) is a peer reviewed journal first published online after indexing scopus in 1982. AMA is published by Farm Machinery Industrial Research Corp and Shin-Norinsha Co. AMA publishes every subjects of general engineering and agricultural engineering. Azerbaijan Medical Journal Gongcheng Kexue Yu Jishu/Advanced Engineering Science Zhonghua er bi yan hou tou jing wai ke za zhi = Chinese journal of otorhinolaryngology head and neck surgery Interventional Pulmonology Zhenkong Kexue yu Jishu Xuebao/Journal of Vacuum Science and Technology Wuhan Ligong Daxue Xuebao (Jiaotong Kexue Yu Gongcheng Ban)/Journal of Wuhan University of Technology (Transportation Science and Engineering) Zhonghua yi shi za zhi (Beijing, China : 1980)
AMA, Agricultural Mechanization in Asia, Africa and Latin America (ISSN: 00845841) is a peer-reviewed journal. The journal covers Agricultural and Biological Sciences and all sort of engineering topic. the journal's scopes are in the following fields but not limited to:
This paper uses analytical calculation analysis and numerical simulation research methods to study the pressure relief of tunnels. Blasting pressure relief achieves the purpose of improving surrounding rock support conditions. The high ground stress of the surrounding rock of the tunnel is transferred to the surrounding rock far away from the surface of the tunnel by loosening blasting to relieve the pressure so as to achieve the purpose of reducing the stress of the surrounding rock and protecting the tunnel. Finally, the simulation results of the internal force of the lining structure are found to be consistent with the analytical research and the numerical research results.
This paper presents the results of an optimization study when grinding SKD11 steel cylinder parts with CBN grinding wheels on CNC milling machines. In this study, the minimum surface roughness is chosen as the objective function. In addition, the influence of process parameters, including the spindel rotation speed, the depth of dressing cut, the feed rate, and the wheel diameter on the surface roughness was investigated. In addition, optimal input parameters to achieve minimum surface roughness were investigated.
This paper introduces an optimization study when electrical discharge machining (EDM) cylindrical parts made of 90CrSi tool steel. The objective of this optimization study is to achieve the maximum material removal speed (MRS). This is an experimental study with the use of the Taguchi method in Minitab 19 software to design the experiment and analyze its results. The impact of the input process parameters, including the pulse on time, the pulse off time, the servo current, and the servo voltage on the MRS was evaluated. In addition, optimal EDM parameters for the maximum MRS were found.
Wire sawing of crystal silicon is one of the most important manufacturing methods for wafer production in photovoltaic and semiconductor industry. Currently, thin wires with smaller wire core, finer abrasive and larger abrasive density are employed in industrial wire sawing to reduce the material kerf loss and increase the quality of wafer surface. This study investigates the influences of feed to wire speed to rate ratio to the cutting depth and material removal at abrasive level when using this type of wires. The model of ingot section profile has been developed allowing the numerical simulations of wire sawing process with different processing and wire parameters. Results show that the brittle cutting always takes place in the wire sawing of silicon. The volume of material removed by brittle cutting could exceed 90% at the bottom cutting zone of the wire even though the percentage of brittle cutting abrasive is less than 20%. In contrast, material removal at the side cutting zone could be pure ductile at low value of feed to wire speed ratio. The comparison of cutting depth distribution in the cutting zone shows a significantly difference in abrasive cutting behaviors. While pure ductile cutting takes place at the side, the process efficiency could be maintained by a number of brittle cutting abrasives at the bottom cutting zone. The results are suitable for determining process parameters for achieving a high material removal rate in sawing direction while keeping the damaged zone in the near-surface region of the wafers as small as possible
Thin diamond wires with smaller steel core, finer abrasives and higher abrasive density are being developed for the wire sawing process in the production of silicon in semiconductor and photovoltaic industry. The use of thinner wires not only increases process efficiency by reducing kerf loss but also improves surface quality by enhancing ductile cutting mechanism in cutting zone. In this paper, a model that considers wire and process parameters is developed to study the cutting depth of abrasives and cutting behaviors during wire sawing process of silicon using thin wires. Simulation results show that when using thin wire with diameter of 100 µm, abrasive size ranging from 40 to 60 µm and abrasive density of 650 pcs/mm2, average cutting depth of abrasives is 0.22 µm and 90.7% of abrasives cutting in ductile mode. It is concluded that material removal shifts from brittle cutting dominance to ductile cutting dominance with the use of thinner wire which results in better sliced surface quality. The proposed model is useful in analyzing of optimal parameters for the wire sawing of silicon wafers.