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| Author(s): |
Henrique Kull Neto
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Mecânica |
| Defense date: | 2016-07-28 |
| Examining board members: |
Anselmo Eduardo Diniz;
Amauri Hassui;
João Batista Fogagnolo;
Eduardo Carlos Bianchi;
Luiz Eduardo de Angelo Sanchez
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| Advisor: | Anselmo Eduardo Diniz |
| Abstract | |
The manufacture of molds and dies involves the milling of complex surfaces of hardened steel. Typically, the deep cavities of such parts are cut using high-speed machining technologies and tools with a high length/diameter ratio. Thus, the milling cutter has a high tendency to vibrate, which may result in cutting edge chipping and/or breakage, and it may also damage the workpiece surface. This work analyzed the tool life, cutting forces and surface roughness in the ball-end milling of a curved (convex) surface of AISI D6 tool steel with hardness of 62 HRC. The goal was to find conditions that provide a good surface quality with long tool life. The work was divided into three stages of experiments. The results of the first stage showed that when machining convex surfaces with the feed direction following a circular path (upward or downward), the roughness and cutting forces are strongly influenced by the feed direction, and a downward strategy provided the best roughness and the smallest cutting forces. In the second stage of testing, when the feed direction followed a linear path (passes with constant Z coordinate) using three different lead angles (-16°, 0° and 16°), the best roughness and the smallest cutting forces were obtained with an upward strategy and lead angle of 0°. In the third stage we evaluated the tool life under the conditions tested in the second stage. Analysis of variance was used for a better understanding of the results. The results showed a close relationship between radial component of the machining force and surface roughness and tool life. The cutting conditions that provided the smallest radial force also generated the best surface finish and longest tool life. Attrition followed by chipping of the cutting edge was the main wear mechanism (AU) | |
| FAPESP's process: | 12/20816-2 - Study of the stability of the milling tool in die and mould manufacturing. |
| Grantee: | Henrique Kull Neto |
| Support Opportunities: | Scholarships in Brazil - Doctorate |