METHOD FOR PRODUCING LONG-LENGTH SEMI-FINISHED PRODUCTS FROM TiNiHf ALLOYS WITH HIGH-TEMPERATURE SHAPE MEMORY EFFECT Russian patent published in 2022 - IPC C22F1/18 C22F1/10 B21C23/08 B21C37/00 B21B3/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, namely to the production of rods from shape memory alloys (SMA) based on titanium nickelide alloyed with hafnium, and can be used for the manufacture of special products with high operating temperatures for various industries, medicine and technology. The method for producing bars from TiNiHf alloy with a high-temperature shape memory effect includes melting ingots and their deformation. Smelted ingots of a given chemical composition with a hafnium content of 1.0-3.0 at. %, nickel 48.5-50.0 at. % and titanium - the rest, from pure initial components Ti, Ni and Hf or from a finished titanium nickelide alloy in the form of a rod and hafnium wire of high purity by electron beam melting in a copper water-cooled stream-type mold, homogenizing annealing of ingots is carried out in a vacuum of at least 10-4 mmHg at a temperature of 1050°C for at least 1 hour. Subsequent deformation is carried out by rotational forging in the temperature range of 750-950°C with single reductions of not more than 7% or rolling in the temperature range of 750-950°C with an elongation ratio per pass of not more than 1.15, and then post-deformation annealing is carried out at a temperature of 400 -550°C for 1-10 hours.

EFFECT: production of bars from TiNiHf alloys of controlled phase and chemical composition, having a high-temperature shape memory effect, as well as high mechanical characteristics.

1 cl, 5 tbl, 2 ex