Flat workpieces have been tested in order to investigate the influence of stress path change (loading mode) while keeping strain path unchanged. These investigations are pertinent to the testing of cold rolled strip...Flat workpieces have been tested in order to investigate the influence of stress path change (loading mode) while keeping strain path unchanged. These investigations are pertinent to the testing of cold rolled strips and to subsequent forming. The workpieces which first compressed by plane strain compression in thickness direction were then tested in perpendicular direction in order to measure the influence of strain and stress path. The tension workpieces came from flat die compression test at different deformation histories. Two different materials were investigated: 18/8 Ti stainless steel and AW-1050 aluminium. The results show that the plastic flow by tension in lengthwise direction after pre-strain by compression in thickness direction will begin at an appreciably lower stress than that of the workpieces unloaded after pre-compression. Comparing with two materials, it can be seen that both 18/8 Ti stainless steel and AW-1050 aluminium behave similarly. The drop in yield stress is lower for AW-1050 aluminium than that for 18/8 Ti stainless steel. However, reloading in different directions than in the precious step results in significantly higher strain hardening.展开更多
预制菜产业高质量发展离不开冷链物流的支撑,当前我国预制菜产业面临冷链物流服务体系不全、服务能力不强、服务成本偏高等问题。面对可预见的万亿级蓝海市场,提升冷链物流对预制菜产业的支撑能力,对实现预制菜产业高质量发展具有重要...预制菜产业高质量发展离不开冷链物流的支撑,当前我国预制菜产业面临冷链物流服务体系不全、服务能力不强、服务成本偏高等问题。面对可预见的万亿级蓝海市场,提升冷链物流对预制菜产业的支撑能力,对实现预制菜产业高质量发展具有重要意义。从基础支撑条件、服务运营能力和提升保障能力3个维度系统构建预制菜产业冷链物流支撑力影响因素指标体系,并应用DEMATEL(Decision Making Trial and Evaluation Laboratory)方法计算各因素的影响度、被影响度、中心度和原因度,定量揭示各因素之间的相互作用关系和重要程度。研究表明,冷链物流企业综合实力、物流装备现代化水平、冷链物流信息化水平、技术创新与转化能力、数据要素赋能水平和土地资金能源保障能力是影响预制菜产业冷链物流支撑力的关键因素。同时,结合关键影响因素,针对性提出提升预制菜产业冷链物流支撑力的路径建议,以此为政府政策制定及企业管理决策提供参考。展开更多
文摘Flat workpieces have been tested in order to investigate the influence of stress path change (loading mode) while keeping strain path unchanged. These investigations are pertinent to the testing of cold rolled strips and to subsequent forming. The workpieces which first compressed by plane strain compression in thickness direction were then tested in perpendicular direction in order to measure the influence of strain and stress path. The tension workpieces came from flat die compression test at different deformation histories. Two different materials were investigated: 18/8 Ti stainless steel and AW-1050 aluminium. The results show that the plastic flow by tension in lengthwise direction after pre-strain by compression in thickness direction will begin at an appreciably lower stress than that of the workpieces unloaded after pre-compression. Comparing with two materials, it can be seen that both 18/8 Ti stainless steel and AW-1050 aluminium behave similarly. The drop in yield stress is lower for AW-1050 aluminium than that for 18/8 Ti stainless steel. However, reloading in different directions than in the precious step results in significantly higher strain hardening.
文摘预制菜产业高质量发展离不开冷链物流的支撑,当前我国预制菜产业面临冷链物流服务体系不全、服务能力不强、服务成本偏高等问题。面对可预见的万亿级蓝海市场,提升冷链物流对预制菜产业的支撑能力,对实现预制菜产业高质量发展具有重要意义。从基础支撑条件、服务运营能力和提升保障能力3个维度系统构建预制菜产业冷链物流支撑力影响因素指标体系,并应用DEMATEL(Decision Making Trial and Evaluation Laboratory)方法计算各因素的影响度、被影响度、中心度和原因度,定量揭示各因素之间的相互作用关系和重要程度。研究表明,冷链物流企业综合实力、物流装备现代化水平、冷链物流信息化水平、技术创新与转化能力、数据要素赋能水平和土地资金能源保障能力是影响预制菜产业冷链物流支撑力的关键因素。同时,结合关键影响因素,针对性提出提升预制菜产业冷链物流支撑力的路径建议,以此为政府政策制定及企业管理决策提供参考。