Method and device for in-situ simultaneous testing of fracture toughness and residual stress of brittle materials

Abstract

The invention discloses an in-situ synchronous test method and device for the fracture toughness and the residual stress of a fragile material. The test method can be used for testing the fracture toughness and the residual stress of a single fragile material and also for testing the fracture toughness and the residual stress of a system interface of a surface fragile coating material. A ratio of equivalent elastic modulus to hardness is calculated according to a volume ratio of residual indentations in two materials, so that the precision of testing on fracture toughness and residual stress of the interface of the fragile material is improved. The load Vickers indentation device researched based on the test method mainly comprises a loading system, an observation system, an image acquisition system, a heating system, a cooling system and a high-temperature gas absorption system. The whole device is simple in structure and easy to operate, and can be used for synchronously measuring the fracture toughness and the residual stress of the fragile material at different temperatures.

Description

technical field [0001] The invention belongs to the technical field of material performance characterization, in particular to an in-situ synchronous testing method and device for fracture toughness and residual stress of brittle materials. Background technique [0002] In the field of new material technology, brittle coating film materials have mechanical, thermal, optical, electrical, magnetic and chemical properties that many substrate materials do not have, and have been widely used in microelectronic devices, magnetic memories, surface coatings and composite materials. It has played an irreplaceable role in the national economy and produced huge economic benefits. However, in the actual application process, due to the large difference between the coating and the substrate, and external factors (such as temperature changes, fatigue loads, high temperature oxidation, medium corrosion, etc.) will gradually affect the bonding performance and strength of the coating and the ...

AI Technical Summary

Problems solved by technology

Existing detection techniques for fracture toughness and residual stress of brittle materials are complex, requiring multiple sets of equipment to be assembled and coordinated for testing, with high professional requirements and cumbersome analysis; mainly focus on testing brittle materials at room temperature, and in-situ testing and characterization at high temperature There are very few experimental equipment for these two material parameter indicators

In terms of experimental testing methods, when the existing indentation method tests the interface fracture toughness and residual stress of brittle coating materials, the length Z of the indentation diagonal perpendicular to the coating interface is used S ,Z C The proportion describes the contribution of the substrate and coating materials in the process of resisting the indentation needle intrusion into the coating system, but does not consider the influence of the substrate and coating materials due to differences in hardness, elastic modulus, plastic deformation, etc., the experimental test low precision

[0005] In summary, there is currently a lack of an efficient and simple experimental test method and matching cutting-edge scientific instruments that can simultaneously test the fracture toughness and residual stress of brittle materials in the range of room temperature to 1600 ° C, which also greatly limits the Layer Product Quality Assurance and Reliability

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