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Homogenization heat treatment of Mg-7.0 wt%Y-1.0 wt%Nd-0.5 wt%Zr alloy

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Rare Metals 2020年第10期39卷 1196-1201页

作者： jing-Bao liu Kui zhang jing-tao han Xing-Gang Li yong-jun Li Ming-Long Ma Jia-Wei Yuan Meng Li State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous MetalsBeijing 100088 China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

The microstructures and mechanical properties of Mg-7.0 wt%Y-1.0 wt%Nd-0.5 wt%Zr magnesium alloy were investigated both in as-cast condition and after homogenization heat treatment by differential scanning calorimetry(DSC),optical microscopy(OM),X-ray diffraction(XRD),scanning electron microscopy(SEM)and hardness *** results indicate that the ascast alloy consists ofα-Mg matrix,Mg24 Y5 and Mg41 Nd5 phases,which are eutectic phases(cubic Y-rich phase).With the increase in homogenization temperature and time,the Mg24 Y5 and Mg41 Nd5 phases are completely dissolved into matrix,and only yttrium of intermetallic compounds leaves around *** homogenization heat treatment,the elements distributed uniformly and the grains grow up not obviously,only yttrium element of intermetallic compounds left around *** optimum homogenization condition is at 537℃for 16 *** mechanical properties are improved after homogenization,with tensile strength ofσb=181 MPa,yielding strength ofσ(0.2)=144 MPa and elongation ofδ=5.5%,which are better than those of as-cast alloy.

关键词： Rare earth magnesium alloy Homogenization Microstructure Hardness

Microstructure and texture evolution of Mg–7Y–1Nd–0.5Zr alloy sheets with different rolling temperatures

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Rare Metals 2020年第11期39卷 1273-1278页

作者： jing-Bao liu Kui zhang jing-tao han Xing-Gang Li yong-jun Li Ming-Long Ma Jia-Wei Yuan Guo-Liang Shi State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous MetalsBeijing100088China School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China

The extruded Mg-7Y-1Nd-0.5Zr(wt%)alloy were performed to the same strain hot rolling with different *** microstructure and texture evolution of the sheets were investigated by optical microscopy(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),and electron back-scattered diffraction(EBSD).The results indicate that the microstructure becomes homogeneous after hot rolling process and precipitated phase distributes at grain boundaries along rolling *** the increase in rolling temperature,the grains of sheet grow *** sheet rolling at 400℃is composed of recrystallization grains,the necklace of the precipitated phase in the grain boundaries and excessive *** structure of necklace of the precipitated phase is fcc structure with lattice constant of a=0.75 *** rolling temperatures increasing from 400 to 450℃,the content of recrystallized grains in volume fraction with relatively random orientations increases *** with the rolling process at 400℃,the amount of precipitated phases is reduced at the grain boundary,and the precipitated phase begins to appear in the grain interior when rolling at 450℃.The structure of the precipitated phase is fcc with lattice constant of a=2.22 *** recrystallization grains begin to grow in the rolling process at 500℃.The basal texture is obviously produced during the rolling process at 400 and 450℃;however,the basal texture is weak in the rolling process at 500℃.

关键词： Rare earth magnesium alloy Rolling Texture Precipitated phase

Transition edge sensor-based detector:from X-ray to γ-ray

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Nuclear Science and Techniques 2022年第7期33卷 61-72页

作者： Shuo zhang jing-Kai Xia tao Sun Wen-tao Wu Bing-jun Wu yong-Liang Wang Robin Cantor Ke han Xiao-Peng Zhou Hao-Ran liu Fu-You Fan Si-Ming Guo jun-Cheng Liang De-Hong Li Yan-Ru Song Xu-Dong Ju Qiang Fu Zhi liu Center for Transformative Science ShanghaiTech UniversityShanghai201210China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai200050China STAR Cryoelectronics 25-A Bisbee CourtSanta FeNM87508-1338USA Shanghai Laboratory for Particle Physics and Cosmology INPAC and Department of Physics and AstronomyShanghai Jiao Tong UniversityShanghai200240China School of Physics Beihang UniversityBeijing100191China Division of Ionizing Radiation National Institute of MetrologyNIMNo.18 Bei San Huan Dong LuChaoyang DistBeijing100029China

A transition edge sensor(TES)is extremely sensitive to changes in temperature,and combined with a high-Z metal of a certain thickness,it can realize high-energy resolution measurements of particles such as X-rays.X-rays with energies below 10 keV have a weak penetrating ability,hence,only gold or bismuth of a few micrometers in thickness can guarantee a quantum efficiency higher than 70%.Therefore,the entire structure of the TES X-ray detector in this energy range can be realized using a microfabrication ***,for X-rays or γ-rays from 10 keV to 200 keV,submillimeter absorber layers are required,which cannot be realized using the microfabrication *** paper first briefly introduces a set of TES X-ray detectors and their auxiliary systems,and then focuses on the introduction of the TES γ-ray detector with an absorber based on a submillimeter lead-tin alloy *** detector achieved a quantum efficiency above 70% near 100 keV and an energy resolution of approximately 161.5 eV at 59.5 keV.

关键词： Synchrotron radiation instrumentation X-ray spectrometers Cryogenic detectors Transition edge sensor

Prognostic value of lymph node metastasis in patients with T1-stage colorectal cancer from multiple centers in China

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World Journal of Gastroenterology 2017年第48期23卷 8582-8590页

作者： Zhen-Qiang Sun Shuai Ma Quan-Bo Zhou Shuai-Xi Yang Yuan Chang xiang-Yue Zeng Wei-Guo Ren Fang-Hai han xiang Xie Fan-Ye Zeng xian-tao Sun Gui-xian Wang Zhen Li Zhi-yong zhang jun-Min Song Jin-Bo liu Wei-Tang Yuan Department of Anorectal Surgery the First Affiliated Hospital of Zhengzhou University Department of Gas-trointestinal Surgery the Affiliated Tumor Hospital of Xinjiang Medical University Department of Gastroenterology the Third Xiangya Hospital of Central South University Department of Gastrointestinal Surgery Sun Yat-sen Memorial Hospital of Sun Yat-sen University Department of Coronary Artery Disease Heart Centerthe First Affiliated Hospital of Xinjiang Medical University Department of Oncology the Affiliated Hospital of Traditional Chinese Medicine of Xinjiang Medical University

AIM To explore the features and prognostic value of lymph node metastasis in patients with T1-stage colorectal cancer(CRC).METHODS In all,321 cases of T1-stage CRC were selected from 10132 patients with CRC who received surgical therapy in six large-scale hospitals in China and were retrospectively analyzed. Univariate and multivariate analyses were performed to analyze the risk factors for lymphatic metastasis. A survival analysis was then performed to analyze the prognostic value of lymph node *** The occurrence rate of T1 stage was 3.17%(321/10132);of these patients,the lymph node metastasis rate was 8.41%(27/321),and the non-lymph node metastasis rate was 91.59%(294/321). Univariate analysis showed that preoperative serum CEA,preoperative serum CA199,preoperative serum CA724,vascular invasion,and degree of differentiation were associated with lymph node metastasis in T1-stage CRC(P < 0.05 for all). Multivariate analysis indicated that preoperative serum CA724,vascular invasion,and degree of differentiation were closely related to lymph node metastasis(P < 0.05 for all). Log-rank survival analysis showed that age,preoperative serum CEA,preoperative serum CA199,vascular invasion,degree of differentiation,and lymph node metastasis(χ2 = 24.180,P < 0.001) were predictors of 5-year overall survival(OS)(P < 0.05 for all). COX regression analysis demonstrated that preoperative serum CA199 and lymph node metastasis(HR = 5.117;P < 0.05;95%CI: 0.058-0.815) were independent prognostic indicators of 5-year OS in patients with T1-stage CRC(P < 0.05 for both). CONCLUSION The morbidity of T1-stage CRC was 3.17% for all CRC cases. Preoperative serum CA724,vascular invasion,and degree of differentiation are independent risk factors for lymph node metastasis. Lymph node metastasis is an independent prognostic factor for OS in patients with T1-stage CRC.

关键词： Colorectal cancer Lymph node metastasis T1 stage Prognosis

Measurement of the neutron total cross section of carbon at the Back-n white neutron beam of CSNS

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Nuclear Science and Techniques 2019年第9期30卷 73-82页

作者： Xing-Yan liu Yi-Wei Yang Rong liu Jie Wen Zhong-Wei Wen Zi-Jie han Zhi-Zhou Ren Qi An Huai-yong Bai Jie Bao Ping Cao Qi-Ping Chen yong-Hao Chen Pin-jing Cheng Zeng-Qi Cui Rui-Rui Fan Chang-Qing Feng Min-Hao Gu Feng-Qin Guo Chang-Cai han Guo-Zhu He yong-Cheng He Yue-Feng He han-Xiong Huang Wei-Ling Huang Xi-Ru Huang Xiao-Lu Ji Xu-Yang Ji Hao-Yu Jiang Wei Jiang han-tao jing Ling Kang Ming-tao Kang Bo Li Lun Li Qiang Li Xiao Li Yang Li Yang Li Shu-Bin liu Guang-Yuan Luan Ying-Lin Ma Chang-jun Ning Bin-Bin Qi Jie Ren Xi-Chao Ruan Zhao-Hui Song Hong Sun Xiao-Yang Sun Zhi-Jia Sun Zhi-Xin Tan Hong-Qing Tang jing-Yu Tang Peng-Cheng Wang Qi Wang tao-Feng Wang Yan-Feng Wang Zhao-Hui Wang Zheng Wang Qing-Biao Wu Xiao-Guang Wu Xuan Wu Li-Kun Xie han Yi Li Yu tao Yu yong-Ji Yu Guo-Hui zhang jing zhang Lin-Hao zhang Li-Ying zhang Qing-Min zhang Qi-Wei zhang xian-Peng zhang Yu-Liang zhang Zhi-yong zhang Ying-Tan Zhao Liang Zhou Zu-Ying Zhou Dan-Yang Zhu Ke-jun Zhu Peng Zhu Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics State Key Laboratory of Particle Detection and Electronics Chinese Academy of Sciences(CAS) Department of Modern Physics University of Science and Technology of China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking University Key Laboratory of Nuclear Data China Institute of Atomic Energy Institute of High Energy Physics Chinese Academy of Sciences(CAS) Spallation Neutron Source Science Center University of South China Northwest Institute of Nuclear Technology Department of Engineering and Applied Physics University of Science and Technology of China Beihang University Xi’an Jiaotong University

To verify the performance of the neutron total cross-sectional spectrometer, the neutron total cross section of carbon is initially measured in the energy range of 1 eV to 20 MeV using the time-of-flight method. The measurement is performed at the Back-n white neutron source with a 76-m time-of-flight path using the China Spallation Neutron Source. A multilayer fast fission chamber with 235U and 238U is employed as the neutron detector. The diameter and thickness of the natural graphite sample are 70 mm and 40 mm, respectively. Signal waveforms are collected using a data acquisition system. Off-line data processing was used to obtain the neutron time-of-flight spectra and transmissions. The uncertainty of the counting statistics is generally approximately 3% for each bin in the energy range of 1–20 MeV. It is determined that the results for the neutron total cross section of carbon obtained using ^235U cells are in good agreement with the results obtained using 238U cells within limits of statistical uncertainty. Moreover, the measured total cross sections show good agreement with the broadening evaluated data.

关键词： CSNS Back-n white neutron source NTOX Neutron total cross section Carbon Multilayer fast fission chamber

Genome-wide signatures of the geographic expansion and breeding of soybean

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Science China(Life Sciences) 2023年第2期66卷 350-365页

作者： Ying-Hui Li Chao Qin Li Wang Chengzhi Jiao Huilong Hong Yu Tian Yanfei Li Guangnan Xing jun Wang yongzhe Gu Xingpeng Gao Delin Li Hongyu Li zhangxiong liu Xin jing Beibei Feng tao Zhao Rongxia Guan yong Guo jun liu Zhe Yan Lijuan zhang Tianli Ge xiangkong Li Xiaobo Wang Hongmei Qiu Wanhai zhang Xiaoyan Luan Yingpeng han Dezhi han Ruzhen Chang Yalong Guo Jochen C.Reif Scott A.Jackson Bin liu Shilin Tian Li-juan Qiu The National Key Facility for Crop Gene Resources and Genetic Improvement(NFCRI)/Key Laboratory of Crop Gene Resource and Germplasm Enhancement(MOA)/Key Laboratory of Soybean Biology(Beijing)(MOA) Institute of Crop ScienceChinese Academy of Agricultural SciencesBeijing 100081China Shenzhen Branch Guangdong Laboratory for Lingnan Modern Agriculture/Genome Analysis Laboratory of the Ministry of Agriculture/Agricultural Genomics Institute at Shenzhen Chinese Academy of Agricultural SciencesShenzhen 518000China Novogene Bioinformatics Institute Beijing 100098China State Key Laboratory of Crop Genetics and Germplasm Enhancement/Cytogenetics Institute Nanjing Agricultural UniversityNanjing 210095China Soybean Research Institute/MOA National Center for Soybean Improvement/MOA Key Laboratory for Biology and Genetic Improvement of Soybean(General)/State Key Laboratory for Crop Genetics and Germplasm Enhancement Nanjing Agricultural UniversityNanjing 210095China College of Agriculture Yangtze UniversityJingzhou 451199China School of Agronomy Anhui Agricultural UniversityHefei 230036China Jilin Academy of Agricultural Sciences Changchun 130119China Hulun Buir Institution of Agricultural Sciences Hulun Buir 021008China Soybean Research Institute Heilongjiang Academy of Agricultural SciencesHarbin 150086China Key Laboratory of Soybean Biology in Chinese Ministry of Education(Key Laboratory of Soybean Biology and Breeding/Genetics of Chinese Agriculture Ministry) Northeast Agricultural UniversityHarbin 150030China Heihe Branch of Heilongjiang Academy of Agricultural Sciences Harbin 150086China State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China Department of Breeding Research Leibniz Institute of Plant Genetics and Crop Plant Research(IPK)Gatersleben DE D-06466Germany Center for Applied Genetic Technologies University of GeorgiaAthens 30602USA Department of Ecology/Tibetan Centre for Ecology and Conservation at WHU-TU/Hubei Key

Soybean is a leguminous crop that provides oil and protein. Exploring the genomic signatures of soybean evolution is crucial for breeding varieties with improved adaptability to environmental extremes. We analyzed the genome sequences of 2,214 soybeans and proposed a soybean evolutionary route, i.e., the expansion of annual wild soybean(Glycine soja Sieb. & Zucc.) from southern China and its domestication in central China, followed by the expansion and local breeding selection of its landraces(G. max(L.) Merr.). We observed that the genetic introgression in soybean landraces was mostly derived from sympatric rather than allopatric wild populations during the geographic expansion. Soybean expansion and breeding were accompanied by the positive selection of flowering time genes, including GmSPA3c. Our study sheds light on the evolutionary history of soybean and provides valuable genetic resources for its future breeding.

关键词： soybean adaptation introgression flowering time breeding

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Study of the response of 10B-doped MCP to wide-energy range neutrons from eV to MeV

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Nuclear Science and Techniques 2024年第8期35卷 132-141页

作者： Qiang Li Li‑Jiao Wang xiang‑Biao Qiu jing‑Wen Li Wei Xu tao Li Ze‑Bin Lin Chang‑jun Ning yong‑Hao Chen Rui‑Rui Fan Kang Sun jing‑Yu Tang Rong zhang han‑tao jing Bo Mei Qi An Hao‑Fan Bai Jiang‑Bo Bai Jie Bao Ping Cao Qi‑Ping Chen Zhen Chen Zeng‑Qi Cui An‑Chuan Fan Chang‑Qing Feng Fan‑Zhen Feng Ke‑Qing Gao Min‑Hao Gu Chang‑Cai han Zi‑Jie han Guo‑Zhu He yong‑Cheng He Yang Hong Yi‑Wei Hu han‑Xiong Huang Wei‑Hua Jia Hao‑Yu Jiang Wei Jiang Zhi‑Jie Jiang Zheng‑Yao Jin Ling Kang Bo Li Chao Li Gong Li Jia‑Wen Li Xiao Li Yang Li Jie liu Rong liu Shu‑Bin liu Guang‑Yuan Luan Bin‑Bin Qi Jie Ren Zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑Hui Song Zhi‑Xin Tan Sheng‑Da Tang Peng‑Cheng Wang Zhao‑Hui Wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Li‑Kun Xie Yi‑Wei Yang han Yi yong‑Ji Yu Guo‑Hui zhang Lin‑Hao zhang Mo‑han zhang Qi‑Wei zhang xian‑Peng zhang Yu‑Liang zhang Yue zhang Zhi‑yong zhang Mao‑Yuan Zhao Lu‑Ping Zhou Zhi‑Hao Zhou Ke‑jun Zhu Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and Electronics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China North Night Vision Science&Technology(Nanjing)Research Institute Co.Ltd. Nanjing 211106China Sino‑French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China USTC Archaeometry Lab University of Science and Technology of ChinaHefei 230026China Northwest Institute of Nuclear Technology Xi’an 710024China University of Chinese Academy of Sciences Beijing 100049China

Neutron-sensitive microchannel plates(nMCPs)have applications in neutron detection,including energy spectrum measurements,neutron-induced cross sections,and neutron imaging.10B-doped MCPs(B-MCPs)have attracted significant attention owing to their potential for exhibiting a high neutron detection efficiency over a large neutron energy *** spatial and temporal resolutions are useful for neutron energy-resolved ***,their practical applications still face many technical *** this study,a B-MCP with 10 mol%10B was tested for its response to wide-energy neutrons from eV to MeV at the Back-n white neutron source at the China Spallation Neutron *** neutron detection efficiency was calibrated at 1 eV,which is approximately 300 times that of an ordinary MCP and indicates the success of 10 B *** factors that caused the reduction in the detection efficiency were simulated and *** neutron energy spectrum obtained using B-MCP was compared with that obtained by other measurement methods,and showed very good consistency for neutron energies below tens of *** response is more complicated at higher neutron energy,at which point the elastic and nonelastic reactions of all nuclides of B-MCP gradually become *** is beneficial for the detection of neutrons,as it compensates for the detection efficiency of B-MCP for high-energy neutrons.

关键词： Neutron radiation image 10B-doped MCP Neutron response Wide-energy range neutrons

Machine learning identifies the risk of complications after laparoscopic radical gastrectomy for gastric cancer

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World Journal of Gastroenterology 2024年第1期30卷 79-90页

作者： Qing-Qi Hong Su Yan yong-Liang Zhao Lin Fan Li Yang Wen-Bin zhang Hao liu He-Xin Lin Jian zhang Zhi-Jian Ye xian Shen Li-Sheng Cai Guo-Wei zhang Jia-Ming Zhu Gang Ji Jin-Ping Chen Wei Wang Zheng-Rong Li jing-tao Zhu Guo-Xin Li jun You Department of Gastrointestinal Oncology Surgery The First Affiliated Hospital of Xiamen UniversitySchool of MedicineXiamen 361001Fujian ProvinceChina Department of Gastrointestinal Surgery Qinghai University Affiliated HospitalXining 810000Qinghai ProvinceChina Department of General Surgery and Center of Minimal Invasive Gastrointestinal Surgery The First Hospital Affiliated to Army Medical UniversityChongqing 400038China Department of General Surgery The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061Shaanxi ProvinceChina Department of General Surgery The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina Department of Gastrointestinal Surgery The First Affiliated Hospital of Xinjiang Medical UniversityUrmuqi 830054Xinjiang Uygur Autonomous RegionChina Department of General Surgery Nanfang HospitalSouthern Medical UniversityGuangzhou 510515Guangdong ProvinceChina Department of Gastrointestinal Surgery Affiliated Hangzhou First People's HospitalZhejiang University School of MedicineHangzhou 310006Zhejiang ProvinceChina Department of Gastrointestinal Surgery Zhongshan Hospital of Xiamen UniversityXiamen 361004Fujian ProvinceChina Department of Surgery The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina Department of General Surgery Unit 4 Zhangzhou Affiliated Hospital of Fujian Medical UniversityZhangzhou 363000Fujian ProvinceChina Department of Gastrointestinal Surgery The Second Affiliated Hospital of Xiamen Medical CollegeXiamen 361021Fujian ProvinceChina Department of Gastrointestinal Nutrition and Hernia Surgery The Second Hospital of Jilin UniversityChangchun 130041Jilin ProvinceChina Department of Digestive Diseases Xijing HospitalAir Force Military Medical UniversityXi'an 710032Shaanxi ProvinceChina Department of Gastrointestinal Surgery Quanzhou First Hospital Affiliated to Fujian Medical UniversityQuanzhou 362002Fujian Provin

BACKGROUND Laparoscopic radical gastrectomy is widely used,and perioperative complications have become a highly concerned *** To develop a predictive model for complications in laparoscopic radical gastrectomy for gastric cancer to better predict the likelihood of complications in gastric cancer patients within 30 days after surgery,guide perioperative treatment strategies for gastric cancer patients,and prevent serious *** In total,998 patients who underwent laparoscopic radical gastrectomy for gastric cancer at 16 Chinese medical centers were included in the training group for the complication model,and 398 patients were included in the validation *** clinicopathological data and 30-d postoperative complications of gastric cancer patients were *** machine learning methods,lasso regression,random forest,and artificial neural networks,were used to construct postoperative complication prediction models for laparoscopic distal gastrectomy and laparoscopic total gastrectomy,and their prediction efficacy and accuracy were *** The constructed complication model,particularly the random forest model,could better predict serious complications in gastric cancer patients undergoing laparoscopic radical *** exhibited stable performance in external validation and is worthy of further promotion in more *** Using the risk factors identified in multicenter datasets,highly sensitive risk prediction models for complications following laparoscopic radical gastrectomy were *** hope to facilitate the diagnosis and treatment of preoperative and postoperative decision-making by using these models.

关键词： Gastric cancer Laparoscopic radical gastrectomy Postoperative complications Laparoscopic total gastrectomy

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软模冲裁工艺数值模拟及变形机理

塑性工程学报 2016年第1期23卷 40-45页

作者：刘倩刘靖张永军韩静涛北京科技大学材料科学与工程学院北京100083

采用试验与有限元模拟相结合的方法研究了软模冲裁与变形机理。通过体积压缩试验将聚氨酯变形转化成压强形式,避免了有限元模拟中构建本构模型与处理耦合变形的问题。利用ABAQUS软件建立了二维轴对称模型,揭示了板料变形机理,分析了浸... 详细信息

采用试验与有限元模拟相结合的方法研究了软模冲裁与变形机理。通过体积压缩试验将聚氨酯变形转化成压强形式,避免了有限元模拟中构建本构模型与处理耦合变形的问题。利用ABAQUS软件建立了二维轴对称模型,揭示了板料变形机理,分析了浸入深度与应力三轴度的变化情况以及板料厚度对冲裁力和塌陷程度的影响。设计制造了软模冲裁装置,从冲裁力-行程曲线方面进行了工艺试验验证。研究结果表明,裂纹在凸模刃口附近产生并单方向扩展;聚氨酯硬度增加可减少冲孔后的塌陷程度,但同时会增大冲裁力;随着材料厚度增加,冲裁力与塌陷程度均明显增大。

关键词：软模冲裁体积压缩断裂准则聚氨酯数值模拟