Research On Preparation Of AlMgB₁₄ Abrasive Grit And Tools

Due to the extremely high hardness,super-hard material can be used to machine hard-to-process materials.Diamond and CBN are most popular super-hard materials,however,diamond is easily graphitizing at high temperatures,CBN is very expensive.Due to the complex manufacturing process,AlMgB₁₄ is one of novel super-hard materials,considered has the potential to machine some hard-to-process metal materials.In this study,the grinding tool based on AlMgB₁₄ is proposed.The synthesized mechanism of AlMgB₁₄,the laser processing rale,and the character AlMgB₁₄ grits crushed are to be investigated,finally the grinding wheel of AlMgB₁₄ is prepared.Firstly in the chapter 3,the synthesis process of AlMgB₁₄ super-hard material was investigated.The powder of AlMgB₁₄ was synthesized by mechanical alloying,the micro-structure of AlMgB₁₄'s powder and composition were analyzed and tested by XRD,SEM and EDS.Through the research,it is found that the composition of raw powder with Al:Mg:B=1.04:1.06:14 can form the best result of AlMgB₁₄'s powderThe bulk of AlMgB₁₄ were synthesized by hot pressing sintering.The micro-structure of AlMgB₁₄'s bulk,the hardness,density and relative density of AlMgB₁₄were analyzed and tested by XRD,SEM and EDS.Through the research,it is found that when the temperature of hot pressing sintering prepared at 1600?,can form the best result of AlMgB₁₄'s bulk.Secondly in the chapter 4,AlMgB₁₄ was etched by pulsed laser,and the effect of processing parameters of laser on the groove was investigated.The micro-structure of AlMgB₁₄'s groove and dimension were analyzed and tested by XRD,SEM and EDS.Through the research,it is found that increasing pulse width and scanning times can increase the dimension of groove,and increasing scanning speed decrease the dimension of groove.Finally in chapter 5,AlMgB₁₄'s bulk materials is crushed into grits.The micro-structure of AlMgB₁₄'s grit and mechanical properties were analyzed and tested by SEM,the resin bond of AlMgB₁₄ grinding tools was prepared by hot press and curing process.