Method of judging morphology of interfacial phase of micro-nano nonuniform material

Abstract

The invention discloses a method of judging morphology of an interfacial phase of a micro-nano nonuniform material and belongs to micro-nano mechanics test methods. When an indentation depth is less than a scratch depth, an indentation can be avoided reaching the interfacial phase, experimental precision is improved, and micro-scale mechanical properties under no influence of peripheral effect areacquired; the nonuniform material is cut and polished to obtain a test surface suitable for nano indentation experiment; an optical microscope of a nano indenter is used to locate a rectangular areaincluding the interfacial phase in a certain range; a right-angle coordinate system containing all scratch paths is established, coordinates of acquisition points on the scratch paths are imported into origin, start and end points of the interfacial phase are connected via lines, and morphology of the interfacial phase in the rectangular area is obtained; the results are imported into SPSS (statistic package for social science) to perform data analysis so as to obtain change law of the morphology of the interfacial phase of the micro-nano nonuniform material. The method enables interfacial phase width of a typical area at certain depth to be effectively judged during nano indentation experiment on a micro-nano material.

Description

technical field [0001] The method for judging the interface phase morphology of micro-nano heterogeneous materials belongs to the micro-nano mechanical test method, especially the method of experimenting with a nano-indentation instrument. Background technique [0002] The interface of micro-nano heterogeneous materials is a riveted and non-uniform boundary, and the interfacial phase is often defined as this riveted area. The nanoindentation experiment carried out in this area obtains the mechanical properties of the two phases of the heterogeneous material, and it is usually necessary to obtain the in-situ performance of a certain material in the heterogeneous material in the experiment. Since the nanoindentation instrument comes with an observation The method is optical microscopy. When the width of the interfacial phase cannot be judged, the nanoindentation mechanical property test of the pure phase is often blind. [0003] Conventionally, the interface contour can be co...

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Problems solved by technology

[0006] First, the conventional contact scanning method (atomic force microscope or nanoindentation instrument) can obtain the contact stiffness or contact force according to the scanning, and then calculate the elastic modulus of the left and right phases, but the measured results will be affected by the surface properties. Influence, and it is impossible to accurately distinguish the test results of different phases of non-uniform materials in a certain area

[0007] Second, the conventional method to obtain the mechanical properties of each phase of a heterogeneous material is to observe the interface between the left phase and the right phase through an optical microscope, and then perform positioning indentation. This method cannot determine whether it is the left phase or the right phase at a certain depth. , the measured results are affected by the uncertain base effect

When observing, the indentation is often inaccurate, and it is necessary to compare images repeatedly for one indentation, which is difficult to analyze and the test efficiency is very low

[0009] Fourth, the conventional scratching method using a nanoindenter controls the scratching process through the change of the normal phase force, which makes the scratching depths different on different phases of heterogeneous materials, that is, when scratching on different phases, the indenter and the test The relative positions of samples are different, which makes it impossible to obtain the width of the interface influence zone by the criterion of contact mechanics

[0010] Fifth, in the conventional method of scratching non-uniform materials by nano-indentation instrument, the effects of base effect and peripheral effect, sample roughness, sub-surface damage caused by grinding and polishing, surface viscosity, protrusion or depression are not constant, The affected area measured by non-constant depth scratches is difficult to analyze, and quantitative conclusions cannot be obtained

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