METHOD OF DEFORMATION-THERMAL TREATMENT TO ESTABLISH FUNCTIONAL PROPERTIES OF MEDICAL CLIPPING DEVICE OF Ti-Ni ALLOY WITH SHAPE MEMORY Russian patent published in 2017 - IPC C22F1/18 A61B18/00 A61B17/03 

FIELD: metallurgy.

SUBSTANCE: invention relates to thermomechanical treatment of shape memory alloys (SMA) and the effect of shape memory effect therein, in particular, the clipping device for creating hemostasis with the possibility of restoration of blood flow in tubular elastic structures of organism when carrying out surgeries. The method of medical clipping device treatment made of Ti-Ni alloy with shape memory effect includes thermomechanical treatment by deformation and aging, and thermomechanical treatment of shape memory effect (SME) and reversible shape memory effect (RSME). During thermomechanical treatment, aging is carried out at temperature of 350-500°C for three stages, at first one of which the clipping device in the form of branches with closed ends is kept for 3-10 hours, and at the second and the third stages of aging the clipping device in the form of branches with the alternately mirror-reflected cut at the angle of 20-50° and the distal ends is kept for 5-180 min, thermomechanical setting of shape memory effect (SME) and reversible shape memory effect (RSME) is carried out by deformation by distancing the branches by angle of 20-90° relative to initial closed state and heating to the temperature in the R-phase existence area with holding for 20-60 s at this temperature, then relieving and subsequent heating until restoration of mould is carried out. Functional properties of medical clipping device are established, creation of temporary or constant hemostasis due to realisation of reversible deformation in the range of 4-7% and generation of reactive force in the range of 1.5-3 H in the course of realisation of one-sided SME when heating up to 40-42°C until the clipping device is fully closed, as well as possibility of subsequent restoration of blood flow in tubular elastic structures of organism due to realisation of reversible shape memory effect with 1-3% value. Angle of opening of branches is realized up to 10° with cooling of clipping device ring to 0°C.

EFFECT: improved properties.

2 cl, 6 dwg, 2 ex