Effect of Microwave Radiation on Pore Structure and Tensile Strength of Metagranulite

doi:10.12068/j.issn.1005-3026.2021.10.012

Abstract

Abstract: In order to reveal the damage law of metagranulite under microwave radiation， the microwave radiation experiments were carried out on metagranulite of gold-bearing ore body from Danyin Mining Co.， Ltd.. The results show that the localized high-temperature melting zone is an iron-rich zone，where a large number of pores formed with pore size up to 0.11mm.Obvious macro cracks and dense micro-fracture networks can be observed near the periphery of the melting zone. With the increase of the distance away from the high temperature zone， the microscopic cracks are obviously reduced， and the porosity gradually decreases. As the microwave radiation time increases， the tensile strength and damage increment decrease continuously. The tensile strength of the rock after microwave radiation depends on the distribution of cracks and the strength and range of the melting zones. The results are of great significance for optimizing the microwave radiation time and improving the efficiency of the microwave radiation cracking.

Key words: microwave radiation; melting zone; pore structure; tensile strength; temperature distribution

CLC Number:

TD80

YU Hong-wen， AN Long， LI Yuan-hui， GAO Chuan-bo. Effect of Microwave Radiation on Pore Structure and Tensile Strength of Metagranulite[J]. Journal of Northeastern University(Natural Science), 2021, 42(10): 1451-1458.

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