• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.05a
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• pp.400-403
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• 2004

A non-heat기leafed steel does not need quenching and tempering processes that are called a heat treatment differently from conventional steel. Since the tensile strength of this steel is higher than 900MPa, a conventional forming process should be changed to incremental forming process such as a cross wedge rolling that requires lower load capacity than conventional ones. In this paper, the cold cross wedge rolling (CWR) die has been designed using CAD/CAE In order to produce near-net-shaped component of ball stud of non-heat-treated cold steel. Finite element analyses were applied in order to investigate process parameters of CWR. Results provide that the stretching angle and the forming angie at knifing zone in CWR process is important parameter to be the stable process under the low friction coefficient condition.

• Textile Coloration and Finishing
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• v.18 no.3 s.88
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• pp.59-64
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• 2006

Knifing parameters specially related to lint generation in the knitting zone such as knitting needles, yarn feed angle and yarn feed speed were investigated with a developed test rig, which simulated the hutting area on the knitting machine. Three different types of needle counts and feeding angles affected tension and the amount of lint that was caused by frictional forces between the yarn and the morphological structure of the needle. However, the yarn feed speed did not affect the lint generation. The results implied that a more advanced test rig was necessary for further study. Also, chemical and mechanical modifications of the kilting elements may be necessary to improve the lint problem.