The invention relates to a forming technology of superfine
thin walled tubular products for vessel stents in the field of treatment, specifically to a method of
processing cobalt-base
alloy superfine
thin walled tubes for novel coronary
artery stents. The method solves the problems of great difficulty in tubular
product processing and low yield of tubular products in a conventional technology. The method for forming finished products comprises the successive technological processes of
smelting,
forging, hot rolling, hot rolling
punching,
honing and cleaning of inner surfaces and outer surfaces, annealing, cold rolling / drawing, annealing, and repeated cold rolling / drawing. During overall process of the repeated cold rolling,
diameter reducing deformation of the tubular products should be controlled in each pass, and match relationship between the
diameter reducing deformation and wall reducing deformation should be well adjusted for guaranteeing that
load carrying capability of inner walls does not exceed sigma b (
breaking strength) and thus for preventing horizontal microscopic breakage. With rough blanks of the tubular products being acquired in high temperature conditions and the
cobalt-base
alloy tubular products being acquired through rolling at a
room temperature, the
processing method guarantees
high dimensional precision, bright and clean inner and outer surfaces and excellent
mechanical property of the tubular products; and is easy to realize and has high
controllability and high economic benefit.