Papers by Author: Y.L. Wang

Abstract: Precision metal sieve-sheets are one of the key components of several high-tech products. Fabrication of the precision sieve-sheets possessing high open area percentage, large thickness and good quality simultaneously has always been a tickler in micro-machining area. In this paper, aiming to manufacture micro-sieves with open areas of about 90% and good quality, micro-electroforming was taken as a major process means, and the technical points and technical difficulties of some key process steps in the preparation of micro-precision sieves were explored emphatically. Meanwhile, operational conditions were optimized and major technological parameters were selected optimally. Using the optimal conditions as well as the optimum parameters, two specifications of hexagon micromesh sieve-sheets whose side length, open-area percent and sheet-thickness was 210μm, 88%, (120±3)μm and 520μm, 92%, (100±2)μm, respectively, were successfully obtained. The electroformed sieves are characterized by flat and smooth surfaces of aperture walls, sharp edge definition, rigid and homogeneous structures and well-distributed mesh.

Abstract: High silicon steel with Si content of 6.5wt.% is perspective to be applied in magnetic devices at high frequencies. It is very hard to produce Fe-6.5wt%Si alloy thin sheet by conventional hot-cold rolling method because of its embrittlement at room temperature resulted from the formation of intermetallic phases like B2 and D03. In this paper, embrittlement mechanism, rolling processes, and magnetic properties for the cold rolled Fe-6.5wt.% Si alloy sheets are discussed. Our study indicates that thermal mechanical treatments can improve the ductility of the Fe-6.5wt.%Si alloy. The Fe-6.5wt.%Si alloy sheets of 0.05 mm thickness can be successfully obtained after hot-cold rolling and heat treatments. Lamination pieces can be punched directly from the sheets. Tensile strength as high as 1048MPa and elongation over 3% were measured at room temperature.