Investigating the changes in the strength of carbonate rocks exposed to microwave energy

Microwave treatment is one of the research topics to solve cutting problems of hard rocks such as low cutting rate and high tool wear. Microwave irradiation creates fractures in the rock body and decreases its strength. Numerous studies have been conducted to ascertain how microwaves affect the strength of rocks. Ten carbonate rocks are examined in this paper to see how microwaving affects their strength. First, unconfined compression and tensile strength tests were conducted on unirradiated dry and saturated core specimens. Following that, the two tests were performed again on samples that had been exposed to radiation for varying amounts of time—between 2 and 6 min—at a microwave power of 6 kW. The results showed that the uniaxial compressive strength loss due to microwave irradiation was between 9.0 and 90.0% and 7.3 and 92.0% for the dry and saturated samples, respectively. Tensile strength loss was between 15.6 and 62.7% and 23.2 and 63.1% for the dry and saturated samples, respectively. The efficiency of treating carbonate rocks with microwaves is significantly impacted by density, porosity, and impurities. Multiple regression equations were derived to estimate the strength losses. Concluding remark is that the strength reductions due to microwaves are significant for carbonate rocks.