Considering their affordability and high strength-to-weight ratio,lightweight aluminium alloys are the subject of intensive research aimed at improving their properties for use in the aerospace industry.This research ...Considering their affordability and high strength-to-weight ratio,lightweight aluminium alloys are the subject of intensive research aimed at improving their properties for use in the aerospace industry.This research effort aims to develop novel hybrid composites based on AA 2014 alloy through the use of liquid metallurgy stir casting to reinforce dual ceramic particles of Zirconium Diboride(ZrB_(2))and Boron Carbide(B4C).The weight percentage(wt%)of ZrB_(2) was varied(0,5,10,and 15),while a constant 5 wt%of B4C was maintained during this fabrication.The as-cast samples have been assessed using an Optical Microscope(OM)and a Scanning Electron Microscope(SEM)with Energy Dispersive Spectroscopy(EDS).The properties such as hardness,tensile strength,and wear characteristics of stir cast specimens were assessed to examine the impact of varying weight percentages of reinforcements in AA 2014 alloy.In particular,dry sliding wear behaviour was evaluated considering varied loads using a pin-on-disc tribotester.As the weight%of ZrB_(2) grew and B4C was incorporated,hybrid composites showed higher hardness,tensile strength,and wear resistance.Notably,the incorporation of a cumulative reinforcement consisting of 15 wt%ZrB_(2) and 5 wt%B4C resulted in a significant 31.86%increase in hardness and a 44.1%increase in tensile strength compared to AA 2014 alloy.In addition,it has been detected that wear resistance of hybrid composite pin(containing 20 wt%cumulative reinforcement)is higher than that of other stir cast wear test pins during the whole range of applied loads.Fractured surfaces of tensile specimens showed ductile fracture in the AA 2014 matrix and mixed mode for hybrid composites.Worn surfaces obtained employing higher applied load indicated abrasive wear with little plastic deformation for hybrid composites and dominant adhesive wear for matrix alloy.Hence,the superior mechanical and tribological performance of hybrid composites can be attributed to dual reinforcement particles being dispersed well and the effective transmission of load at this specific composition.展开更多
研究了硬质合金表面Ni P 纳米Ti(C,N)化学复合镀工艺以及热处理对复合镀层性能影响的规律。结果表-);2)较好的明:1)施镀工艺中各因素对镀速影响的显著性顺序是:温度→pH值→纳米Ti(C,N)加入量→χ(Ni2+ H2PO2施镀工艺为:28g L氯化镍、... 研究了硬质合金表面Ni P 纳米Ti(C,N)化学复合镀工艺以及热处理对复合镀层性能影响的规律。结果表-);2)较好的明:1)施镀工艺中各因素对镀速影响的显著性顺序是:温度→pH值→纳米Ti(C,N)加入量→χ(Ni2+ H2PO2施镀工艺为:28g L氯化镍、25.76g L次亚磷酸钠,50g L氯化铵、45g L柠檬酸钠,0.001g LPbCl2,6g L纳米Ti(C,N),pH=10,温度为80℃。3)Ni P 纳米Ti(C,N)复合镀层较优的热处理工艺为:在400℃保温150min。采用所推荐的施镀和热处理工艺,获得了硬度是硬质合金基体硬度的2.16倍的Ni P 纳米Ti(C,N)复合镀层。并对以上结果产生的原因进行了简单讨论。展开更多
文摘Considering their affordability and high strength-to-weight ratio,lightweight aluminium alloys are the subject of intensive research aimed at improving their properties for use in the aerospace industry.This research effort aims to develop novel hybrid composites based on AA 2014 alloy through the use of liquid metallurgy stir casting to reinforce dual ceramic particles of Zirconium Diboride(ZrB_(2))and Boron Carbide(B4C).The weight percentage(wt%)of ZrB_(2) was varied(0,5,10,and 15),while a constant 5 wt%of B4C was maintained during this fabrication.The as-cast samples have been assessed using an Optical Microscope(OM)and a Scanning Electron Microscope(SEM)with Energy Dispersive Spectroscopy(EDS).The properties such as hardness,tensile strength,and wear characteristics of stir cast specimens were assessed to examine the impact of varying weight percentages of reinforcements in AA 2014 alloy.In particular,dry sliding wear behaviour was evaluated considering varied loads using a pin-on-disc tribotester.As the weight%of ZrB_(2) grew and B4C was incorporated,hybrid composites showed higher hardness,tensile strength,and wear resistance.Notably,the incorporation of a cumulative reinforcement consisting of 15 wt%ZrB_(2) and 5 wt%B4C resulted in a significant 31.86%increase in hardness and a 44.1%increase in tensile strength compared to AA 2014 alloy.In addition,it has been detected that wear resistance of hybrid composite pin(containing 20 wt%cumulative reinforcement)is higher than that of other stir cast wear test pins during the whole range of applied loads.Fractured surfaces of tensile specimens showed ductile fracture in the AA 2014 matrix and mixed mode for hybrid composites.Worn surfaces obtained employing higher applied load indicated abrasive wear with little plastic deformation for hybrid composites and dominant adhesive wear for matrix alloy.Hence,the superior mechanical and tribological performance of hybrid composites can be attributed to dual reinforcement particles being dispersed well and the effective transmission of load at this specific composition.
文摘 研究了硬质合金表面Ni P 纳米Ti(C,N)化学复合镀工艺以及热处理对复合镀层性能影响的规律。结果表-);2)较好的明:1)施镀工艺中各因素对镀速影响的显著性顺序是:温度→pH值→纳米Ti(C,N)加入量→χ(Ni2+ H2PO2施镀工艺为:28g L氯化镍、25.76g L次亚磷酸钠,50g L氯化铵、45g L柠檬酸钠,0.001g LPbCl2,6g L纳米Ti(C,N),pH=10,温度为80℃。3)Ni P 纳米Ti(C,N)复合镀层较优的热处理工艺为:在400℃保温150min。采用所推荐的施镀和热处理工艺,获得了硬度是硬质合金基体硬度的2.16倍的Ni P 纳米Ti(C,N)复合镀层。并对以上结果产生的原因进行了简单讨论。
