Effects of binder compounds,powder shape and molding pasameters

• Main Authors: Hwang, Wey, 黃衛
• Other Authors: K.S.Hwang
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/23624394614617881477

碩士 === 國立臺灣大學 === 材料科學與工程學研究所 === 85 === Abstract There were three objectives in this study. The first one was to optimize the composition for a binder consisting of polyethylene, wax, stearic acid. The second one was to evaluate three stainless steel powders with different size and shape. The third one was to examine the effect of major molding parameters on the rheology and physical properties of molded compacts. In the first experiment, four binder compositions (LDPE:PW: SA=30:65:5,35:60:5,40:55:5,and 45:50:5)were evaluated. The results on green strength,sagging during debinding, tolerance control,and defect percentage showed that the binder ratio of 40:55:5 is the best. In the second experiment, three stainless steel powders designated as A, M, and P were examined for their spiral flow length, green strength, shape retention capability, swelling during solvent debinding, tolerance and density stability. Results showed that water atomized powder P is the best considering the overall performance. The optimum sintering temperature were 1370℃ and 1320℃ for powder A and M, respectively. For powder P,the adequate sintering temperature ranged from 1320 to 1370℃. In the third experiment, feedstock after one molding run showed the best rheology property compared to the fresh and second recycled feedstock. The length of holding pressure time and the rotation speed were found to be insignificant to the green properties. But, the density and weight of green specimens increased with increasing holding pressure. The tolerance control was influenced by the holding pressure and the powder shape. Key words:316L S.S. powder ,solvent debinding,dimension stability ,defects ,debinding slumping,powder shape , solvent debinding dilation ,binder ,processing parameter.