Research On The Tribochemical Removal Of Granite Under The Action Of Bionic Complexing Agents

Currently,rock breakage and removal in rock engineering is mainly performed by using tools.When encountering rocks with high hardness and abrasiveness such as granite,tool wear is very severe,thereby causing low rock-breaking efficiency,which seriously affects the quality and efficiency of rock engineering construction.In fact,there exist organisms in nature which drill rocks through mechanical destruction coupling with chemical erosion.This phenomenon is called bioerosion,and its chemical action does not involve strong acid and alkali,which is expected to be applied in rock engineering construction.Inspired by natural bioerosion,therefore,a series of bionic neutral complexing agents were prepared,and their effects on the tribochemical removal behavior of granite were investigated.The findings from this study will provide theoretical support for the development of rock breaking technology.In this thesis,three bionic neutral complexing agents were prepared using three organic acids,citric acid,tartaric acid,and oxalic acid,and referred to as CA,TA and OA,respectively.The influence of bionic neutral complexing agents on the tribochemical removal behavior of granite was investigated using surface morphology and hardness characterizations,reciprocating sliding friction and wear tests,and TBM rock-breaking simulation tests.The main results and conclusions are as follows:(1)Without obvious corrosion on H13 steel(a common rock-breaking tool material),the three bionic complexing agents,CA,OA and TA,promoted the tribochemical removal of granite through changing the friction and wear behavior of granite,and the agent of OA had the most obvious effect among them.Compared with strong inorganic acids such as,the as-prepared complexing agents had more significant effects on the friction and wear behavior of granite surface.(2)The bionic complexing agents led to the corrosive damage of the crystal structure of the mineral particles contained within granites including quartz,potash feldspar and biotite through the complexations of mineral cations,thereby reducing the grain size of minerals.This was the essential reason for the weakening of the tribological properties of granite surface.(3)The bionic complexing agents had significantly increased corrosion effect on granite mineral particles by in combination with industrial complexing agents,where there was no obvious corrosion on H13 steel.They not only effectively promoted the material removal of granite surface,but also reduced the wear of H13 tool by providing certain lubrication effect for the tool-rock interface under TBM rock-breaking simulation tests condition.