IJAT Vol.6 No.5 pp. 591-596
doi: 10.20965/ijat.2012.p0591


Reducing Weld Line by Heating Mold Surface with Heater Embedded by Laser Metal Sintering

Takeshi Yoneyama*, Satoshi Abe**, and Michiru Miyamaru***

*School of Mechanical Engineering, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan

**Panasonic Corporation Eco Solutions company, 1048 Kadoma, Osaka 571-8686, Japan

***Miyamaru Precision Mold Co., 1-31 Higashi-kayatsume, Kanazawa 920-0209, Japan

May 20, 2012
July 26, 2012
September 5, 2012
laser metal sintering, injection mold, rapid prototype, heat and cool, weld-line

Thin micro sheath heaters are embedded just under the surface of a mold during the process of laser metal sintering. This is to reduce the weld line on the molded surface by heating it just before the injection. Laser metal sintering process was interrupted at a level just below the final height to make grooves into which to insert micro sheath heaters. After the heaters were installed, laser metal sintering continued over the heaters until the final mold height was reached. Through this process, micro heaters 1 mm in diameter were embedded 2 mm under the mold surface. The mold surface was heated to 20°C over the cooling temperature by the embedded heaters just before the injection, and heating was stopped after the injection. By so doing, the weld line on the molded surface was reduced, while the cooling time was the same as in molding without such heating.

Cite this article as:
Takeshi Yoneyama, Satoshi Abe, and Michiru Miyamaru, “Reducing Weld Line by Heating Mold Surface with Heater Embedded by Laser Metal Sintering,” Int. J. Automation Technol., Vol.6, No.5, pp. 591-596, 2012.
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Last updated on May. 16, 2022