Ti(C,N)/TiN multi-element-layer films was deposited on aluminium alloy substrates by using multi-arc ion plating. The microhardness of the films was 2000HV0.i which was nearly 21 times of that of the substrates. XRD a...Ti(C,N)/TiN multi-element-layer films was deposited on aluminium alloy substrates by using multi-arc ion plating. The microhardness of the films was 2000HV0.i which was nearly 21 times of that of the substrates. XRD analysis show that the main composition of the composite films system were Ti(C,N), TiN, Al3Ti, Al and a little Ti2N. The presence of MjTi new phase in the interface of the films/substrates indicated some metallurgical bonding between them, which implies higher adhesive strength of the films/substrates system. Pin-on-disc tests showed that the wear resistance of the substrates was improved substantially. However, the coefficient of friction of the films/substrate system was high (u=0.66), which resulted in the wear of the counterparts. To reduce the coefficient of friction, nanometer lubrication dry films was applied on top of the multi-element-layer films to form composite films system and subsequent wear tests showed that the resulting composite films led to reduction of the coefficient of friction from 0.66 to 0.16. Meanwhile, wear mass loss of the counterpart was reduced from 1.29 mg to 0.02 mg, so that increased wear resistance and reduced friction effects were achieved.展开更多
在高内压循环作用下地下储气库衬砌易产生裂缝与渗透通道,密封层受力与裂缝控制问题尤为关键。基于有限-离散元方法(finite-discrete element method,简称FDEM),建立了连续-非连续的围岩-衬砌-密封层整体模型,系统研究了平钢板与波拱两...在高内压循环作用下地下储气库衬砌易产生裂缝与渗透通道,密封层受力与裂缝控制问题尤为关键。基于有限-离散元方法(finite-discrete element method,简称FDEM),建立了连续-非连续的围岩-衬砌-密封层整体模型,系统研究了平钢板与波拱两类钢衬及预设缝设计参数对衬砌裂缝演化与密封性能的影响。结果表明,平钢板型密封层应力水平和裂缝数量较高,整体性差,预设缝改善衬砌开裂与密封结构受力作用有限;波拱型结构能显著降低峰值应力并改变裂缝分布,使得裂缝多集中在波拱底部,整体裂缝数量减少,但波拱处的裂缝开裂宽度更大。采用波拱+预设缝相结合的方案可进一步均匀化开裂,减少密封钢衬应力。随着波拱和预设缝数量增加,应力分布趋于均匀,裂缝扩展受控,但最大裂缝宽度呈先减后增趋势,钢衬应力模式由拉应力向弯-剪应力转变。当缝设于拱底时,裂缝可沿预设路径均匀扩展,并可结合防排水措施降低渗透风险。总体而言,波拱+预设缝复合设计在引导裂缝、释放应变和提升密封渗透性能方面具有显著优势,为储气库密封-衬砌协同优化设计提供参考。展开更多
文摘Ti(C,N)/TiN multi-element-layer films was deposited on aluminium alloy substrates by using multi-arc ion plating. The microhardness of the films was 2000HV0.i which was nearly 21 times of that of the substrates. XRD analysis show that the main composition of the composite films system were Ti(C,N), TiN, Al3Ti, Al and a little Ti2N. The presence of MjTi new phase in the interface of the films/substrates indicated some metallurgical bonding between them, which implies higher adhesive strength of the films/substrates system. Pin-on-disc tests showed that the wear resistance of the substrates was improved substantially. However, the coefficient of friction of the films/substrate system was high (u=0.66), which resulted in the wear of the counterparts. To reduce the coefficient of friction, nanometer lubrication dry films was applied on top of the multi-element-layer films to form composite films system and subsequent wear tests showed that the resulting composite films led to reduction of the coefficient of friction from 0.66 to 0.16. Meanwhile, wear mass loss of the counterpart was reduced from 1.29 mg to 0.02 mg, so that increased wear resistance and reduced friction effects were achieved.
文摘在高内压循环作用下地下储气库衬砌易产生裂缝与渗透通道,密封层受力与裂缝控制问题尤为关键。基于有限-离散元方法(finite-discrete element method,简称FDEM),建立了连续-非连续的围岩-衬砌-密封层整体模型,系统研究了平钢板与波拱两类钢衬及预设缝设计参数对衬砌裂缝演化与密封性能的影响。结果表明,平钢板型密封层应力水平和裂缝数量较高,整体性差,预设缝改善衬砌开裂与密封结构受力作用有限;波拱型结构能显著降低峰值应力并改变裂缝分布,使得裂缝多集中在波拱底部,整体裂缝数量减少,但波拱处的裂缝开裂宽度更大。采用波拱+预设缝相结合的方案可进一步均匀化开裂,减少密封钢衬应力。随着波拱和预设缝数量增加,应力分布趋于均匀,裂缝扩展受控,但最大裂缝宽度呈先减后增趋势,钢衬应力模式由拉应力向弯-剪应力转变。当缝设于拱底时,裂缝可沿预设路径均匀扩展,并可结合防排水措施降低渗透风险。总体而言,波拱+预设缝复合设计在引导裂缝、释放应变和提升密封渗透性能方面具有显著优势,为储气库密封-衬砌协同优化设计提供参考。
