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1.
00Cr25Ni7Mo4N超级双相不锈钢热加工性能的研究   总被引:1,自引:0,他引:1  
通过Gleeble热模拟机对真空感应炉熔炼的00Cr25Ni7Mo4N锻材进行高温拉伸和单道次及连续4道次压缩试验。结果表明,在900~1 250℃的范围内随温度提高和在950~1 100℃时随道次递增,00Cr25Ni7Mo4N钢的最大变形抗力逐渐下降;在1 050~1 250℃时,00Cr25Ni7Mo4N钢的变形抗力较低,断面收缩率高于60%,具有较好的热塑性;当应变速率为10/s且温度高于1 000℃,及应变速率为50/s且温度高于1 100℃时,钢的热加工性较好。  相似文献   

2.
采用Gleeble 1500热模拟试验机研究了0.008 7%~0.150 0%N对热轧0Cr18Ni9N钢(%:0.044~0.049C、0.41~0.51Si、1.46~1.52Mn、17.92~18.15Cr、9.09~9.24Ni、0.01~0.03Ti)以应变速率5×10~(-3)s~(-1)和1s~(-1)在800~1300℃的拉伸和压缩性能的影响,并分析了N含量对该钢动态再结晶性能的影响。结果表明,随着N含量的增加,该钢断面收缩率显著下降,同时其最佳热塑性的温度区间提高;当N含量低于0.0500%时,最佳热塑性区间为950~1100℃;而当N含量为0.0800%~0.1500%时,则为1150~1250℃。  相似文献   

3.
采用Gleeble 1500热模拟试验机研究了0.008 7%~0.1500%N对热轧0Cr18Ni9N钢(%:0.044~0.049C、0.41~0.51 si、1.46~1.52Mn、17.92~18.15Cr、9.09~9.24Ni、0.01~0.03Ti)以应变速率5×10-3s-1和18-1在800~1 300℃的拉伸和压缩性能的影响,并分析了N含量对该钢动态再结晶性能的影响.结果表明,随着N含量的增加,该钢断面收缩率显著下降,同时其最佳热塑性的温度区间提高;当N含量低于0.0500%时,最佳热塑性区间为950~1100℃;而当N含量为0.0800%~0.150 0%时,则为1150~1 250℃.  相似文献   

4.
00Cr25Ni7Mo4N超级双相不锈钢的高温变形行为   总被引:8,自引:0,他引:8  
采用热/力模拟实验方法研究了00Cr25Ni7Mo4N超级双相不锈钢(SDSS)在900~1 200℃、应变速率为0.1~10 s-1条件下的热变形及组织变化,讨论了热变形参数对流变应力和显微组织的影响.结果表明,在上述变形条件下,00Cr25Ni7Mo4N超级双相不锈钢中铁素体的软化机制与Z参数有关,且随着Z参数减小,铁素体软化机制由动态回复向动态再结晶转变;该钢的表观应力指数为3.51,热变形表观激活能为492 kJ/mol.  相似文献   

5.
超塑性奥氏体-铁素体双相不锈钢00Cr25Ni7Mo3N的研制   总被引:1,自引:0,他引:1  
张兰  王立新  任学平 《特殊钢》2005,26(6):44-46
通过电弧炉-电渣重熔工艺开发研制了成分为(%):0.021C,24.16Cr,7.21Ni,2.87Mo,0.17N,0.48Cu超塑性双相不锈钢00Cr25Ni7Mo3N。试验结果表明,00Cr25Ni7Mo3N超塑性双相不锈钢的耐孔蚀性和耐缝隙腐蚀性远高于传统的304L和316L奥氏体不锈钢。在变形温度960℃、应变速率2×10-3/s时,00Cr25Ni7Mo3N超塑性双相不锈钢的最高延伸率为960%,该钢超塑性变形的均匀性优于TC4钛合金,可显著减轻构件的重量。  相似文献   

6.
铸态 00Cr22Ni5Mo3N 的热塑性   总被引:3,自引:0,他引:3  
采用Gleeble1500对00Cr22Ni5Mo3N铸态试样进行了热拉伸和热压缩试验,找出了铸态00Cr22Ni5Mo3N的最佳热塑性温度区间为1 150~1 250 ℃,并且分析了该钢的热塑性与其组织、性能的关系.  相似文献   

7.
研究了00Cr22Ni5Mo3N钢的热扭转性能,结果表明,通过对化学成分和扭转温度的合理控制,可以使00Cr22Ni5Mo3N钢获得良好的热塑性,并使其变形抗力小于1Cr18Ni9Ti钢.根据试验结果制订了生产工艺,采用热穿孔工艺成功试制出00Cr22Ni5Mo3N钢大口径厚壁无缝管.  相似文献   

8.
冷却速率对00Cr25Ni7Mo4N超级双相 不锈钢析出相的影响   总被引:1,自引:0,他引:1  
王晓峰  陈伟庆  郑宏光 《钢铁》2009,44(1):63-0
 利用热膨胀仪测定了00Cr25Ni7Mo4N超级双相不锈钢的CCT曲线,结合金相法、显微硬度法、X射线衍射法分析了冷却速率对00Cr25Ni7Mo4N超级双相不锈钢σ析出相的影响。结果表明,00Cr25Ni7Mo4N双相不锈钢热处理或热加工温度应控制在1050 ℃以上;冷却速率越小,σ相析出量越多,显微硬度也越高;钢在冷却过程中要以大于4800 ℃/h的冷却速率通过600~1000 ℃区域,从而避免σ脆性相的析出。  相似文献   

9.
介绍了00Cr25Ni7Mo4N超级双相不锈钢的化学成分及重点元素的作用,给出了00Cr25Ni7Mo4N超级双相不锈钢的物理性能、力学性能、耐蚀性能,给出了00Cr25Ni7Mo4N超级双相不锈钢的显微组织,叙述了该钢的热处理工艺、冷热加工工艺、焊接工艺,列出了该钢的适用技术条件、产品形状及用途,介绍了国内该钢近年来的一些研究情况。  相似文献   

10.
李惠  宋志刚  丰涵  郑文杰  张颖 《特殊钢》2015,36(3):57-60
通过Thermo-Calc热力学计算、金相和电化学方法分析和研究了1 050~1120℃固溶的00Cr21Ni2Mn5N、00Cr22Ni5Mo3N、00Cr25Ni7Mo3N、00Cr27Ni7Mo5N四种典型超低碳双相不锈钢在5001~100℃时效后σ相的析出规律和σ相含量对四种双相不锈钢点蚀电位的影响。结果表明,σ相析出量随着时效温度的升高呈现先增加后减小的趋势,并且随着双相不锈钢中铬-钼含量(/%)依次20.98-0.03,22.41-3.16,25.30-3.46,26.69-4.74递增时,σ相析出量峰值递增,依次为4.9%,22.5%,27.0%,40.5%,同时σ相完全溶解温度提高,依次为660,950,1 060,1100℃;σ相析出量越大超低碳双相不锈钢耐点蚀性能越低,4种钢的σ相析出峰值对应的Eb100值依次为-94.0,100.1,260.2,117.7 mV。  相似文献   

11.
Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.  相似文献   

13.
鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".  相似文献   

14.
张兴强  叶运福 《冶金设备》2005,(6):71-72,47
针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。  相似文献   

15.
转炉炉壳热应力分析   总被引:5,自引:1,他引:4  
任学平  郭志强  邹家祥 《炼钢》2001,17(6):47-49
根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。  相似文献   

16.
In this paper is treated the fundamental problematic of the fracture of the diaphysis of the tibia and the therapeutic results after the conservative and operative treatment are confronted. Among 518 patients with 433 open fractures and 35 with closed fractures of the diaphysis of the tibia, successful treatment of more 2/3 was obtained in the period from 1968 to 1972. Following our casuistics and literature, whose results are similar, we find out that the average total treatment of the osteosynthesis of the fracture of the diaphysis was shortened for 2,5 months depending upon the type and the localisation of the fracture. Apolied methods of the operative and conservative and conservative treatment in relation to the velocity of the medical cure as well as to the extreme anatomical-functional results are analised. We noticed that osteosynthesis, made by the intermedullary nail and the extension of the canals or by a small AO table, by the achieved stability makes conditions of immediate motions and an early rehabilitation. Because of that it gives the best functional results.  相似文献   

17.
18.
Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.  相似文献   

19.
通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。  相似文献   

20.
为了编制实用性强的基地建设行动方案,首先,确定参与式发展的主体,搭建一个"决策框架";其次,针对行动目标,提出不同参与主体,如管理者、农民、消费者等团队与个人的目标及行动内容;最后,工作应向重塑伙伴式合作关系,挖掘农民自我发展潜力,完成三大角色的转换,打造农业基地文化等方向推进.  相似文献   

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