Permeability Characteristics and Applications of Plastic Injection Molding Fabricated by Metal Laser Sintering Combined with High Speed Milling
Michio Kojima*, Hiroyuki Narahara*, Yoshiyuki Nakao*, Hirofumi Fukumaru*, Hiroshi Koresawa*, Hiroshi Suzuki*, and Satoshi Abe**
*Department of Mechanical Information Science and Technology, Kyushu Institute of Technology
680-4 Kawazu Iizuka-shi, Japan.
**Matsushita Electric Works, Ltd., 1048, Kadoma, Kadoma-shi, Japan.
This paper describes the results of fundamental experiments conducted by injection mold with permeability fabricated by Metal Laser Sintering Combined with High Speed Milling. Metal Laser Sintering Combined with High Speed Milling is attracting attention as a new mold fabrication approach. This machining method combines the metallic powder layer fabrication method with high-speed cutting. Since this process does not have the problem of tool L/D in usual cutting, it provides outstanding shape machining performance of deep ribs etc. Moreover, with this processing method, sintered density can be controlled by changing the exposure conditions of the laser beam, and gas permeable structures can also be manufactured. This fabrication method does not require the mold to be divided. From these features, this method is expected to offer such advantages as quick delivery of molds and low manufacturing costs. However, little is known about the application of laser sintered metallic molds which have gas permeability structure to plastic injection molding, and the practical use of these molds is not easy. The aim of this research was therefore to investigate the gas permeable structures realized by laser sintered metallic mold in plastic injection molding The results confirmed that permeable injection molds are effective for influencing residue air in products.