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Ballistic performance of titanium-based layered composites made using blended elemental powder metallurgy and hot isostatic pressing
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作者 Pavlo Markovsky Jacek Janiszewski +5 位作者 Dmytro Savvakin Oleksandr Stasyuk Bartosz Fikus Victor Samarov Vianey Ellison Sergey V.Prikhodko 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期1-14,共14页
Metal matrix composites tiles based on Ti-6Al-4V(Ti64)alloy,reinforced with 10,20,and 40(vol%)of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy(BEPM)and then bonded to... Metal matrix composites tiles based on Ti-6Al-4V(Ti64)alloy,reinforced with 10,20,and 40(vol%)of either TiC or TiB particles were made using press-and-sinter blended elemental powder metallurgy(BEPM)and then bonded together into 3-layer laminated plates using hot isostatic pressing(HIP).The laminates were ballistically tested and demonstrated superior performance.The microstructure and properties of the laminates were analyzed to determine the effect of the BEPM and HIP processing on the ballistic properties of the layered plates.The effect of porosity in sintered composites on further diffusion bonding of the plates during HIP is analyzed to understand the bonding features at the interfaces between different adjacent layers in the laminate.Exceptional ballistic performance of fabricated structures was explained by a significant reduction in the residual porosity of the BEPM products by their additional processing using HIP,which provides an unprecedented increase in the hardness of the layered composites.It is argued that the combination of the used two technologies,BEPM and HIP is principally complimentary for the materials in question with the abilities to solve the essential problems of each used individually. 展开更多
关键词 Metal matrix composites Powder metallurgy Titanium hydride powder Master alloy Titanium carbide Titanium boride Hot isostatic pressing Ballistic tests
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Orthogonal tests of copper-clad aluminum bimetal continuous casting by nitrogen pressure core-illing 被引量:4
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作者 Xue Zhiyong Liang He +1 位作者 Yu Wanhua Wu Chunjing 《China Foundry》 SCIE CAS 2013年第6期385-390,共6页
To provide theoretical basis and practical guidance for preparing composite rods by direct continuous casting, copper-clad aluminum composite rods of external copper layer diameter 12 mm and inner aluminum core diamet... To provide theoretical basis and practical guidance for preparing composite rods by direct continuous casting, copper-clad aluminum composite rods of external copper layer diameter 12 mm and inner aluminum core diameter 8 mm were manufactured. Orthogonal tests consisted of three factors and three levels were carried out to research the effects of melting copper temperature, continuous casting speed and nitrogen pressure on the performance of composite rods. Results showed that nitrogen pressure is the most important factor in influencing the surface quality; continuous casting speed is the most important factor in influencing copper & aluminum inter diffusion amount. Nitrogen pressure can noticeably improve the surface quality and make the rods easily be drawn out, but the surface quality does not show visible improvement when the nitrogen pressure is above 0.05 MPa. Measured by tests, the compound layer can be divided into three types according to its cladding layer degree: deficient cladding, normal cladding and excess cladding. The diameter of normal copper-clad aluminum composite rods can be successfully drawn less than 0.6 mm without annealing. 展开更多
关键词 copper-clad aluminum nitrogen pressing continuous casting orthogonal test
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Orthogonal tests of lead-clad tin bimetal continuous casting by air pressure core-filling 被引量:1
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作者 梁贺 赵永龙 +1 位作者 臧勃林 吴春京 《Journal of Central South University》 SCIE EI CAS 2011年第5期1340-1348,共9页
To provide theoretical basis and practical guidance for preparing composite rods of external diameter no larger than 12 mm by directly continuous casting,low melting point materials of lead and tin were selected to pr... To provide theoretical basis and practical guidance for preparing composite rods of external diameter no larger than 12 mm by directly continuous casting,low melting point materials of lead and tin were selected to prepare composite rods of external diameter 12 mm and inner diameter 8 mm with air pressing core filled continuous casting process.The orthogonal tests consisting of three factors and three levels were designed to investigate the parameters of melting lead temperature,continuous casting speed and air pressure that affect the performance of the composite rods.The results show that melting lead temperature is the most important factor that influences the solid/liquid interface location;continuous casting speed is the most important factor that influences the surface quality and lead and tin inter-diffusion amount;air pressure can improve the surface quality obviously and make the rods easily drawn out,but the surface quality cannot get obvious improvement when the air pressure is above 0.03 MPa.The composite rods have excellent surface quality,obvious intermediate layer,even thick clad,and metallurgical bonding interface under the condition of melting lead temperature of 375 °C,continuous casting speed of 10 mm/min,and air pressure of 0.03 MPa. 展开更多
关键词 lead-clad tin air pressing core-filling continuous casting orthogonal test
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Deformation mechanism at impact test of Al-11% Si alloy processed by equal-channel angular pressing with rotary die 被引量:2
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作者 马爱斌 Y. NISHIDA +3 位作者 江静华 N. SAITO I. SHIGEMATSU A. WATAZU 《中国有色金属学会会刊:英文版》 EI CSCD 2007年第1期104-109,共6页
Al-11%Si(mass fraction)alloy was transformed into a ductile material by equal-channel angular pressing(ECAP)with a rotary die.Two mechanisms at impact test,slip deformation by dislocation motion and grain boundary sli... Al-11%Si(mass fraction)alloy was transformed into a ductile material by equal-channel angular pressing(ECAP)with a rotary die.Two mechanisms at impact test,slip deformation by dislocation motion and grain boundary sliding,were discussed.The ultrafine grains with modified grain boundaries and the high content of fine particles(<1μm)were necessary for attaining high absorbed energy.The results contradict the condition of slip deformation by dislocation motion and coincide with that of grain boundary sliding.Many fine zigzag lines like a mosaic were observed on the side surface of the tested specimens.These observed lines may show grain boundaries appeared by the sliding of grains. 展开更多
关键词 铝合金 变形行为 微观结构 晶界滑动
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On-line Detection of Gas Pipeline Based on the Real-Time Algorithm and Network Technology with Robot
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作者 鄢波 颜国正 +3 位作者 丁国清 周斌 付西光 左建勇 《Journal of Donghua University(English Edition)》 EI CAS 2004年第5期93-97,共5页
The detection system integrates control technology, network technology, video encoding and decoding, video transmiss-ion, multi-single chip microcomputer communication, dat-abase technology, computer software and robo... The detection system integrates control technology, network technology, video encoding and decoding, video transmiss-ion, multi-single chip microcomputer communication, dat-abase technology, computer software and robot technology. The robot can adaptively adjust its status according to diameter (from 400 mm to 650 mm) of pipeline. The maximum detection distance is up to 1 000 m. The method of video coding in the system is based on fractal transformation. The experiments show that the coding scheme is fast and good PSNR. The precision of on-line detection is up to 3% thickness of pipeline wall. The robot can also have a high precision of location up to 0.03 m. The control method is based on network and characterized by on-line and real-time. The experiment in real gas pipeline shows that the performance of the detection system is good. 展开更多
关键词 on-line control control based on network fractal video coding(FVC) Non-Destructive testing (NDT)
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香蕉茎秆轧辊式压榨脱水机设计与试验
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作者 徐树英 陈淦兴 +1 位作者 林常 刘世豪 《农业工程学报》 EI CAS CSCD 北大核心 2024年第19期21-32,共12页
针对香蕉收获后剩余的香蕉茎秆废弃物难处理以及蕉农的劳动强度大和效率低等问题,该研究设计了一种香蕉茎秆轧辊式压榨脱水机,适用于需收集香蕉茎秆汁液和茎秆纤维的南方香蕉种植地区。该机构根据茎秆易缠绕、难粉碎或难切片的特性采用... 针对香蕉收获后剩余的香蕉茎秆废弃物难处理以及蕉农的劳动强度大和效率低等问题,该研究设计了一种香蕉茎秆轧辊式压榨脱水机,适用于需收集香蕉茎秆汁液和茎秆纤维的南方香蕉种植地区。该机构根据茎秆易缠绕、难粉碎或难切片的特性采用逐渐开口减小的四级轧辊式压辊,并对压辊表面进行了花纹设计。根据结构紧凑、功率消耗少、动力分配合理等原则,设计了同步四级压辊转速以及驱动输料和排渣机构的传动机构。通过力学分析得到了压辊间隙作为压辊对茎秆压力大小的影响因素之一。利用ANSYS/LS-DYNA模块对香蕉茎秆进行压榨脱水分析,验证压榨机构压榨脱水的可行性和可靠性。香蕉茎秆压榨脱水试验结果表明香蕉茎秆脱水率在28.00%~46.29%左右,所设计的压榨脱水机极大地减少了香蕉茎秆的体积和质量,减少了蕉农的劳动强度和运输成本,便于香蕉茎秆废弃物的后续的高值化利用。 展开更多
关键词 农业机械 设计 试验 香蕉茎秆 压榨脱水
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不同尺寸HMX基压装装药的烤燃特性
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作者 董泽霖 屈可朋 +2 位作者 胡雪垚 肖玮 王奕鑫 《高压物理学报》 CAS CSCD 北大核心 2024年第2期138-147,共10页
为了研究装药尺寸对压装装药烤燃特性的影响,针对HMX基压装装药,建立了压装装药烤燃过程的计算模型,利用Fluent软件对不同装药尺寸的烤燃样弹进行了数值模拟,计算了不同升温速率下装药尺寸对压装装药点火位置、响应温度和响应时间的影... 为了研究装药尺寸对压装装药烤燃特性的影响,针对HMX基压装装药,建立了压装装药烤燃过程的计算模型,利用Fluent软件对不同装药尺寸的烤燃样弹进行了数值模拟,计算了不同升温速率下装药尺寸对压装装药点火位置、响应温度和响应时间的影响规律。结果表明:在同一升温速率下,HMX基压装炸药装药长径比为1.0时,装药中心响应温度均为最高;装药长径比大于1.0时,装药中心点火温度均随长径比的增加而降低;当长径比增大到一定程度时,装药中心的响应温度趋于恒值。装药的点火位置由升温速率和装药尺寸共同决定,且装药端面与曲面的传热量之比与长径比的平方成反比。当升温缓慢或长径比较小时,装药的点火位置位于装药中心;当升温速率较高且长径比较大时,装药的点火位置逐渐远离装药中心。 展开更多
关键词 HMX基炸药 压装装药 烤燃试验 装药尺寸
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烟草垄体分层施肥土壤镇压试验与肥料颗粒偏移分析
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作者 裴宜坤 宋强龙 +6 位作者 陈雪婷 夏月庆 陈永 汤胜美 马少帅 刘新萍 张秀丽 《河南农业大学学报》 CAS CSCD 北大核心 2024年第4期654-662,共9页
【目的】研究烟草起垄分层施肥镇压复合作业时,镇压压强P与土壤下陷量B的关系、土壤下陷量B与据表层150 mm处的土壤坚实度M的关系及土壤内部肥料颗粒的偏移情况,为镇压装置与分层施肥装置关键结构的设计提供理论基础。【方法】通过改变... 【目的】研究烟草起垄分层施肥镇压复合作业时,镇压压强P与土壤下陷量B的关系、土壤下陷量B与据表层150 mm处的土壤坚实度M的关系及土壤内部肥料颗粒的偏移情况,为镇压装置与分层施肥装置关键结构的设计提供理论基础。【方法】通过改变施加载荷的大小进行镇压试验,测量垄体表层土壤下陷量B和距离表层150 mm处的土壤坚实度M,获得P-B曲线和B-M曲线,根据烟草移栽农艺要求确定土壤下陷量B和压强P的范围。通过EDEM仿真,得到土壤镇压作业时内部颗粒的偏移情况。【结果】得到了在符合作物生长需求的条件下,镇压产生的土壤下陷量B的范围为5~33 mm,相应施加在土壤表面的压强P为5~23 kPa;在土壤下陷量B为25 mm时,分层施肥肥料颗粒向下偏移量分别为20.2、15.1、7.7、4.8 mm,与镇压试验结果误差为10.0%~14.6%。最后通过田间试验进行验证。【结论】根据土壤压缩及内部颗粒偏移规律设计分层施肥镇压装置,垄内分层施肥深度稳定,整形效果良好,可为镇压装置及垄内分层施肥装置的设计提供参考。 展开更多
关键词 烟草垄体 镇压试验 土壤下陷量 分层施肥 镇压装置
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基于ANSYS瓦楞纸板等效力学性能研究
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作者 彭子腾 郝天照 +2 位作者 王瑞 姜洋 张鹏 《包装工程》 CAS 北大核心 2024年第21期192-199,共8页
目的为提升瓦楞纸板压缩性能仿真效率,采用有限元方法替代试验测试,以节省时间与成本,减少环境污染,促进可持续发展,为瓦楞纸箱的优化设计提供决策依据。方法从箱板纸和瓦楞原纸性能出发,对瓦楞纸板的最小单元进行1∶1建模分析,通过ANSY... 目的为提升瓦楞纸板压缩性能仿真效率,采用有限元方法替代试验测试,以节省时间与成本,减少环境污染,促进可持续发展,为瓦楞纸箱的优化设计提供决策依据。方法从箱板纸和瓦楞原纸性能出发,对瓦楞纸板的最小单元进行1∶1建模分析,通过ANSYS对瓦楞纸板压缩性能进行仿真求解并对结果进行分析,找到一种瓦楞纸板力学性能的等效方法。利用瓦楞纸板的等效力学性能对瓦楞纸板模型进行一定程度的简化,以达到在保证一定求解精度的情况下,提高求解速度的目的。结果箱板纸和瓦楞原纸的力学性能可用双线性等向强化模型等效;瓦楞纸板压缩过程分为4个阶段:弹性、屈服、平台、密实化。通过ANSYS Workbench的Static Structure模块进行仿真,与试验结果对比,仿真能有效预测其压缩性能。简化瓦楞纸板为均质长方体后,仿真结果显示,简化模型平压有限元分析求解时间减少13%~60%,内存减少37%~62%,且模型尺寸越大,减少得越多。结论使用该方法对瓦楞纸板的压缩性能进行仿真,解决了以往通过反复试验来优化包装设计的弊端,能节约时间,降低瓦楞纸板的生产成本和减少环境污染,实现可持续发展。 展开更多
关键词 瓦楞纸板 平压试验 有限元分析 简化模型 等效力学
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高压断路器用灭弧喷口的近净成形优化工艺研究
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作者 刘雅娟 赵晔 +5 位作者 侯亚峰 侯国良 舒明泽 许东杰 王亚祥 陈蕊 《绝缘材料》 CAS 北大核心 2024年第6期49-53,共5页
为了解决异形喷口压制过程中毛坯开裂的问题,本研究自主设计了一种近净成形异形喷口压制模具,并对模具的结构进行了逐步的优化,同时基于已有的压制工艺对压制压力、压制速度、保压时间等工艺参数进行了优化。结果表明:通过对异形压制模... 为了解决异形喷口压制过程中毛坯开裂的问题,本研究自主设计了一种近净成形异形喷口压制模具,并对模具的结构进行了逐步的优化,同时基于已有的压制工艺对压制压力、压制速度、保压时间等工艺参数进行了优化。结果表明:通过对异形压制模具结构的逐步优化,喷口圆弧过渡区域和V型垫块底部的开裂问题得到解决。通过对压制工艺的优化,喷口毛坯各位置密度一致性得到了提升,圆弧过渡区域的力学性能、电气性能与两端基本无差别,且采用本工艺压制的喷口原材料损耗降低了约30%。 展开更多
关键词 灭弧喷口 聚四氟乙烯 异形模具 压制试验
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基于Kano-FAST-E的鞋面压合机优化设计
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作者 周红宇 张林涵 +2 位作者 刘津圻 姜雯馨 薛爽 《包装工程》 CAS 北大核心 2024年第8期308-317,共10页
目的降低鞋面压合机设备作业过程中的失误率、优化人机交互体验。方法基于Kano模型调研分析作业人员与企业经理对当前设备的使用感受及需求;利用FAST理论重新定义设备的功能区域并指导设计展开;基于人机工程学理论(E),对设计方案的功能... 目的降低鞋面压合机设备作业过程中的失误率、优化人机交互体验。方法基于Kano模型调研分析作业人员与企业经理对当前设备的使用感受及需求;利用FAST理论重新定义设备的功能区域并指导设计展开;基于人机工程学理论(E),对设计方案的功能布局和结构尺寸进行优化,提升人机操作效率;利用眼动试验对改进前后的功能布局进行对比分析验证,并借助李克特量表对设计方案进行用户满意度评价。结果完成鞋面压合机的优化设计实践,提升了设备的人机性能和用户满意度,有效提高了作业人员认读效率、减少视觉疲劳和错误操作。结论改进后的鞋面压合机赋予了工人更加安全、高效且人性化的操作模式,验证了Kano-FAST-E的设计策略对该设备的人机优化设计具有指导意义,也为同类设备的开发实践提供参考。 展开更多
关键词 鞋面压合机 KANO模型 FAST理论 人机工程 眼动试验
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辊压机减速机空负荷试车工艺设计
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作者 林志业 《水泥工程》 CAS 2024年第4期54-56,共3页
针对辊压机减速机在维修装配完毕后,受自身外形结构和固定位置的限制,无法实现空负荷试车或无法满转速试车的问题,对辊压机减速机空负荷试车工艺进行改进设计,改进后的新工艺解决了原试车过车中存在的问题。
关键词 辊压机减速机 试车 设计
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掩护式前部放顶煤液压支架选型设计与可靠性研究
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作者 徐建 《煤矿机械》 2024年第12期20-23,共4页
为解决土耳其IMBAT矿使用的四柱低位放顶煤支架出现的放煤效果不理想、拔后柱严重、外形尺寸大下井受限、前部顶板冒顶严重、顶板管理难度大等问题,结合矿方地质条件,提出一种适应此类地质条件的掩护式前部放顶煤液压支架。介绍了该液... 为解决土耳其IMBAT矿使用的四柱低位放顶煤支架出现的放煤效果不理想、拔后柱严重、外形尺寸大下井受限、前部顶板冒顶严重、顶板管理难度大等问题,结合矿方地质条件,提出一种适应此类地质条件的掩护式前部放顶煤液压支架。介绍了该液压支架的选型过程以及主要参数和结构特点,并对整架进行了偏转和扭转有限元分析。经样机研制及26000次压架试验,验证了该支架布局及结构的合理性,丰富了具备此类地质条件的综放开采液压支架应用案例。 展开更多
关键词 前部放煤 选型 有限元分析 压架试验
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机器人与伺服压力机控制应用研究
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作者 李冰洁 《电气传动自动化》 2024年第3期17-20,5,共5页
利用系统的非线性动力学,对机器人和工业伺服压力机机构进行了实例分析,并对机器人系统和伺服曲柄压力机进行了识别和仿真研究,获得了系统的动态行为。根据应用所要求的不同运动轨迹,在系统上研究了软计算技术,并且运用传统PID控制技术... 利用系统的非线性动力学,对机器人和工业伺服压力机机构进行了实例分析,并对机器人系统和伺服曲柄压力机进行了识别和仿真研究,获得了系统的动态行为。根据应用所要求的不同运动轨迹,在系统上研究了软计算技术,并且运用传统PID控制技术,通过PSO-NN(粒子群优化神经网络)、BP(反向传播)、PSOPID、PID、CasFF(级联前馈)等控制方法,实现了控制目的。 展开更多
关键词 机器人 伺服压力机 控制技术 实验测试
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关于冷压接线端子拉力试验标准优化的建议
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作者 杨军 《铁道车辆》 2024年第1期132-137,共6页
目前铁路行业中冷压接线端子拉力试验标准众多,但普遍存在内容不全面、试验方法不一致、拉力值标准不统一等现象,具体表现为:同一标准拉力值适用于所有类型端子,同一端子在不同的标准中有不同的试验方法,在相同的试验方法下,不同的标准... 目前铁路行业中冷压接线端子拉力试验标准众多,但普遍存在内容不全面、试验方法不一致、拉力值标准不统一等现象,具体表现为:同一标准拉力值适用于所有类型端子,同一端子在不同的标准中有不同的试验方法,在相同的试验方法下,不同的标准对同一端子的拉力值要求也不一致,这造成技术人员在实际应用中经常感到困惑,不知如何选择,同时,相应的拉力试验标准也未能真正体现出标准的意义。针对这一问题,文章首先结合行业常用标准及现场实际应用情况对铁路行业常用接线端子进行了分类;其次分析对比了常用标准适用范围,明确各类端子与各标准的适配性;然后在适配的前提下对存在不同试验方法的同类端子提出了一种新的拉力试验方法以兼容不同标准;接着对相同拉力试验方法下的不同标准拉力值进行对比分析,按最严格的原则整理出统一的拉力值标准;最后对拉力试验方法和拉力值标准进行汇总,形成常用端子拉力试验标准优化建议以供参考。 展开更多
关键词 冷压接线端子 拉力试验 端子压接 拉脱力 保持力
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V弯试验设备的自动化改造及效率提升
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作者 李文煌 《现代制造技术与装备》 2024年第9期204-206,共3页
V弯试验是评估镀锌板性能的重要方法,但传统设备依靠人工操作,效率低且存在安全隐患。因此,文章提出一种V弯试验设备的自动化改造方案,通过集成机械手、优化夹具设计、升级控制系统等,实现装夹、弯曲、压平等全流程自动化。结果显示,改... V弯试验是评估镀锌板性能的重要方法,但传统设备依靠人工操作,效率低且存在安全隐患。因此,文章提出一种V弯试验设备的自动化改造方案,通过集成机械手、优化夹具设计、升级控制系统等,实现装夹、弯曲、压平等全流程自动化。结果显示,改造后的设备单件效率提升30%~50%,角度重复精度改善64%~66%,在提质增效方面效果显著。 展开更多
关键词 V弯试验 自动化改造 机械手 伺服压机 镀锌板
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智能加药系统在煤泥水处理中的研究与应用
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作者 李鹏波 申迎松 +3 位作者 王晓坤 宋志兵 郭晋强 乔鹏 《选煤技术》 CAS 2024年第1期79-86,共8页
煤泥水处理是选煤厂生产过程中的关键环节。为了解决煤泥水处理过程中存在的药剂浓度不稳定、人工经验依赖性强、药剂调整滞后、操作效率低等问题,王坡选煤厂在基于煤泥水处理现状分析的基础上,进行了加药系统智能化改造,通过对助滤剂... 煤泥水处理是选煤厂生产过程中的关键环节。为了解决煤泥水处理过程中存在的药剂浓度不稳定、人工经验依赖性强、药剂调整滞后、操作效率低等问题,王坡选煤厂在基于煤泥水处理现状分析的基础上,进行了加药系统智能化改造,通过对助滤剂和絮凝剂制备及加药装置进行设计,构建参数检测系统,完善控制方案,实现了煤泥水系统的高效运行。生产实践表明,智能加药系统持续稳定运行,减员3人,实现了无人值守;浓缩效率提高了2.19个百分点,底流固体产率提高了0.76个百分点,压滤上料时间缩短了500s/班;絮凝剂用量降低了8.56%,助滤剂用量降低了10.25%;减少了生产事故的发生。智能加药系统的应用,每年可为王坡选煤厂节约人工成本、电费和材料成本约87万元,经济效益显著。 展开更多
关键词 智能加药 智能加药系统 无人值守 参数检测系统 浓缩效率 药剂用量 上料时间
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Laser ultrasonic testing for near-surface defects inspection of 316L stainless steel fabricated by laser powder bed fusion 被引量:3
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作者 Ting Dai Xiao-jian Jia +6 位作者 Jun Zhang Jin-feng Wu Yi-wei Sun Shu-xian Yuan Guan-bing Ma Xiao-jing Xiong Hui Ding 《China Foundry》 SCIE CAS 2021年第4期360-368,共9页
The laser powder bed fusion(L-PBF)method of additive manufacturing(AM)is increasingly used in various industrial manufacturing fields due to its high material utilization and design freedom of parts.However,the parts ... The laser powder bed fusion(L-PBF)method of additive manufacturing(AM)is increasingly used in various industrial manufacturing fields due to its high material utilization and design freedom of parts.However,the parts produced by L-PBF usually contain such defects as crack and porosity because of the technological characteristics of L-PBF,which affect the quality of the product.Laser ultrasonic testing(LUT)is a potential technology for on-line testing of the L-PBF process.It is a non-contact and non-destructive approach based on signals from abundant waveforms with a wide frequency-band.In this study,a method of LUT for on-line inspection of L-PBF process was proposed,and a system of LUT was established approaching the actual environment of on-line detection to evaluate the method applicability for defects detection of L-PBF parts.The detection results of near-surface defects in L-PBF 316L stainless steel parts show that the crack-type defects with a sub-millimeter level within 0.5 mm depth can be identified,and accordingly,the positions and dimensions information can be acquired.The results were verified by X-ray computed tomography,which indicates that the present method exhibits great potential for on-line inspection of AM processes. 展开更多
关键词 additive manufacturing 316L stainless steel on-line inspection laser ultrasonic testing non-destructive testing
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Deformation Behavior of Hot Isostatic Pressing FGH96 Superalloy 被引量:2
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作者 刘玉红 李付国 喻宏波 《Transactions of Tianjin University》 EI CAS 2006年第4期281-285,共5页
The deformation behavior of hot isostatic pressing (HIP) FGH96 superalloy was characterized in the temperature range of 1000-1100 ℃ and strain rate range of 0. 001-0. 1 s^-1 using hot compression testing. The flow ... The deformation behavior of hot isostatic pressing (HIP) FGH96 superalloy was characterized in the temperature range of 1000-1100 ℃ and strain rate range of 0. 001-0. 1 s^-1 using hot compression testing. The flow curves of HIP FGH96, superalloy during hot deformation was analyzed systematically. The results show that deformation temperature, strain rate and strain are the main influence factors on flow stress of HIP FGH96 superalloy during hot deformation. The flow stress displays a peak at a critical strain and then decreases with further increase in strain. For a given strain, the flow stress decreases with the increase of deformation temperature, and increases with the increase of strain rate. A mathematical model of these flow curves was established through regression analysis and taking the strain as a modification factor. The calculated stress values agree well with the experimental values. 展开更多
关键词 powder metallurgical superalloy hot isostatic pressing compression testing mathematical model regression analysis
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Hot Forging and Hot Pressing of AlSi Powder Compared to Conventional Powder Metallurgy Route 被引量:1
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作者 Sayed Moustafa Walid Daoush +1 位作者 Ahmed Ibrahim Erich Neubaur 《Materials Sciences and Applications》 2011年第8期1127-1133,共7页
Aluminum silicon alloy of composition (Al-25%Si-3%Ni-1%Fe-2%Cu) was atomized using water atomization. The powders were cold compacted in a die to produce green cylinder compacts. Four consolidation processes were appl... Aluminum silicon alloy of composition (Al-25%Si-3%Ni-1%Fe-2%Cu) was atomized using water atomization. The powders were cold compacted in a die to produce green cylinder compacts. Four consolidation processes were applied, namely;conventional sintering at 500℃, sintering followed by hot forging to obtain pistons, one step hot forging into pistons, and hot pressing. The microstructure of the sintered specimens showed inter-granular pores and oxide layers on particle interfaces of 84% relative density. When the sintered specimens were hot forged, both the inter-granular pores and oxide layers on particle interfaces almost disappeared and the relative densities increased up to about 95%. The same microstructure is also obtained for the one step forged specimens, but the relative densities increased to about 97%. However, the hot pressing specimens showed the presence of oxide layers on particle surfaces as well as few isolated pores. The relative density of the hot pressed specimens was about 90%. Hardness and ultimate compression strength were measured. It is noted that the strongest bulk materials are those made by hot forging, followed by those made by hot pressing and the weakest bulk materials are those made by conventional sintering. 展开更多
关键词 Aluminum-Silicon Alloy Powder METALLURGY HOT FORGING HOT pressING Hardness Compression test
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