Method for ultrasonic-assistance laser near-net shape forming of titanium-nickel alloy gradient material

Abstract

The invention discloses a method for ultrasonic-assistance laser near-net shape forming of a titanium-nickel alloy gradient material and belongs to the technical field of additive manufacturing. The titanium-nickel based alloy gradient material is manufactured through an ultrasonic-assistance laser near-net shape forming system in an additive manufacturing mode. The method includes the steps thatan ultrasonic generator is fixed to a machine tool working table, a pre-heater is fixed to the ultrasonic generator, and a base plate is fixed to the pre-heater. During forming, the ratio of two typesof powder is changed constantly with the volume fraction of 10% as the step length, and gradient transition from a titanium alloy to a nickel-based alloy is achieved step by step. Through ultrasonicassistance and pre-heating, the defects such as air holes and shrinking holes in a sample can be reduced, and the brittle phase is uniformly distributed on a substrate,; and meanwhile the hardness, the abrasion resistance and other properties of the substrate can be improved, the temperature gradient can be reduced during forming through assistant pre-heating, and the possibility of cracks is greatly lowered. The gradient material prepared through the method is not limited by the shape and the size, and the production efficiency is improved while the cost is reduced.

Description

technical field [0001] The invention belongs to the technical field of additive manufacturing, and in particular relates to a method for ultrasonic-assisted laser near-net-shape titanium-nickel alloy gradient material. Background technique [0002] With the continuous development of my country's aerospace technology, there are more and more special performance requirements for key components on high-speed or even ultra-high-speed aircraft. At present, materials widely used in aerospace include titanium alloys and nickel-based superalloys; titanium alloys have the advantages of high specific strength, good fatigue resistance, and small linear expansion coefficient, etc., but their disadvantages are poor high temperature oxidation resistance, so under high temperature conditions Its application is limited; nickel-based superalloys have high strength and oxidation corrosion resistance at high temperatures, but the disadvantage is that their density is nearly twice that of titan...

AI Technical Summary

Problems solved by technology

[0007] In order to solve the problems of multiple structural defects (cracks, pores, shrinkage cavities, etc.), uneven structure, and limited manufacturing size of gradient materials prepared by traditional processing methods, the present invention provides an ultrasonic-assisted laser near-net-shaped titanium-nickel-based alloy gradient material Compared with other methods, this method not only reduces the temperature gradient, but also compensates the attenuation of ultrasound passing through solid / liquid media by continuously increasing the ultrasonic power density. This method is extremely effective on the basis of improving the efficiency of traditional manufacturing methods. It greatly reduces the possibility of pores and cracks inside the sample, and at the same time improves the hardness and wear resistance of the sample; it can meet the high-strength-lightweight service requirements of the material, reduce the cost, and improve the accuracy

Images