MAGNESIUM-BASED ALLOY PIPE AND METHOD FOR MANUFACTURING THE SAME

PROBLEM TO BE SOLVED: To provide a magnesium-based alloy pipe which is long and has a high dimensional accuracy, an excellent mechanical property and a small diameter, and a method for manufacturing the alloy pipe.SOLUTION: A raw material 1 comprising a magnesium-based alloy is extrusion-molded by use of an upper die 2 and a lower die 3. The upper die 2 is equipped with plural open holes 21 for feeding the raw material 1 comprising the magnesium-based alloy at equal intervals on a circumference, and a columnar projection 22, which is so positioned at a center of the plural open holes 21 as to be surrounded by the open holes 21, on an exit side of the open holes 21. The lower die 3 is equipped with recesses 31 which are commonly communicated with the plural open holes 21 of the upper die 2, and an open hole 32 which is positioned at a center of the recesses 31 and into which the columnar projection 22 of the upper die 2 is inserted with provision of a tube molding gap.SELECTED DRAWING: Figure 1 【課題】長尺で、寸法精度が高く、機械的性質に優れた小径のマグネシウム基合金管及びその製造方法を提供すること。【解決手段】マグネシウム基合金からなる原材料１を、円周上に等角度間隔にマグネシウム基合金の原材料１を供給する複数の貫通孔２１及びこの貫通孔２１の出口側に貫通孔２１に囲まれるように複数の貫通孔２１の中心に位置する円柱形状の突起２２を備えた上型２と、この上型２の複数の貫通孔２１の出口に共通して連通する形状の凹部３１及びこの凹部３１の中心に位置し、上型２の円柱形状の突起２２が管成形隙間を設けて挿入される貫通孔３２を備えた下型３とからなる成形型を用いて、押出成形する。【選択図】図１