热压条件下不同预合金粉末对金刚石性能的影响OA

Objectives:Metal-bonded diamond cutting tools are extensively utilized in industrial applications such as stone cutting,metal processing,and mining due to their superior hardness and wear resistance.However,the use of metallic elements in diamond tools presents certain limitations.Specifically,poor wetting of diamond at elevated temperatures results in inadequate adhesion,while elemental powders can adversely affect the surface morphology of diamond at lower temperature conditions.This study aims to investigate the effects of pre-alloyed powders under various hot pressing conditions on the performance of diamond tools,with a particular emphasis on compressive strength,surface morphology,and Raman spectroscopy analysis.Additionally,the influence of different alloy powders on the mechanical properties of diamond tools is explored,with the objective of understanding how alloy composition and sintering temperature impact their structural integrity and performance under high-temperature conditions.Methods:In this experiment,diamond samples are prepared using nickel-based,copper-based,and iron-based pre-alloyed powders.These materials are selected due to their potential influence on the interaction between the binder and the diamond matrix during the sintering process.The choice of these alloys is based on their anticipated effects on diamond behavior,particularly regarding high-temperature stability and corrosion resistance.The diamonds are hot-pressed and sintered at various temperatures to assess the impact of temperature and alloy composition on diamond properties.After sintering,compressive strength is measured through single particle testing,and surface morphology is analyzed using scanning electron microscopy(SEM).Additionally,Raman spectroscopy is employed to investigate structural changes,particularly those associated with graphitization and high-temperature exposure.Results:The sintering temperature significantly impacts the performance of diamond tools.An increase in temperature leads to intensified corrosion of the diamond surface,resulting in a decrease in compressive strength.At 900℃,the compressive strength of a single particle decreases to 97.2 N,indicating substantial degradation of the diamond structure at elevated temperatures.This suggests that higher sintering temperatures can damage diamond materials and reduce tool effectiveness.In addition to temperature,the composition of pre-alloyed powder plays a crucial role in determining the mechanical properties of diamonds.Nickel-based pre-alloyed powders containing Cr promote the formation of chromium carbide(Cr3C2)at high temperatures,which further weakens the structural integrity of diamonds.In contrast,copper-based powders exhibit a protective effect,maintaining the mechanical properties of diamonds at elevated temperatures.Raman spectroscopy further confirms that Co exerts a stronger graphitization effect on diamonds,compromising their structural stability.Conclusions:The sintering temperature and the composition of pre-alloyed metal powder are key factors affecting the performance of diamonds.High sintering temperature can cause significant degradation of diamonds,while alloy composition can alleviate or exacerbate this effect.The Cu element in iron-based pre-alloys has a protective effect on diamond,to some extent protecting the corrosion from Fe element on the surface of diamond.Due to its similar unit cell constant to diamond,Co is more likely to promote the conversion of diamond to graphite at high temperatures.The Cr element in nickel-based pre-alloys reacts with diamond,resulting in a significant decrease in the compressive strength of diamond at higher temperatures.These findings emphasize the importance of selecting the optimal alloy composition and sintering conditions to improve the performance of diamond tools,especially in high-temperature applications in industrial environments.In addition,alloy selection plays a crucial role in maintaining the mechanical integrity of diamond tools during usage.Future research can explore more alloy powders and deepen our understanding of their interaction with diamond,in order to further optimize the performance of diamond tools in various industrial applications.