PURPOSE: To obtain sufficient strength in cylinder tube even if it is thin and to attain its lightening in weight and nonmagnetization.
CONSTITUTION: This cylinder tube is constituted of an intermediate cylinder 3 made of heat resistant aluminum alloy for casting in which an internal layer 2 constituted of a fiber reinforced composite material is integrated and an external cylinder 4 made of a high strength aluminum alloy for working chilled and engaged with an intermediate cylinder 3, and this fiber reinforced composite material is the one in which a heat resistant aluminum allay for casting is blended with carbon fibers in the ratio of 15 to 50vol.% to the whole body of the fiber reinforced composite material, potassium titanate whiskers are blended in the ratio of 20 to 50vol.% to the carbon fibers, and they are compounded in such a manner that the total content of the carbon fibers and potassium titanate whiskers is regulated to the ratio of 18 to 60vol.% to the whole body of the fiber reinforced composite material. Thus, its specific wear amt., the coefficient of friction, hardness and logarithmic decrement are improved by the internal layer 2, and its strength to gaseous pressure is secured by the external cylinder body 4.
TOMONO YUTAKA
KOTAKE SEIICHI
HOTTA RYUICHI
CHIYOU GIHIN
HITACHI SHIPBUILDING ENG CO