热处理工艺对1Cr11Co3W3NiMoVNbNB钢析出相及性能的影响

采用SEM、TEM、化学相分析、热力学计算等手段研究了不同回火工艺下的超超临界汽轮机组叶片用1Cr11Co3W3NiMoVNbNB马氏体耐热钢中析出相的分布和性能。热力学计算表明,该叶片在620℃温度服役,合金中M23C6相的形成能要比Laves相的形成能低,M23C6相会在服役初期大量析出,但随着服役时间增加合金中的Laves相大量析出,析出数量将超过M23C6相。合金经过淬火、高温回火处理后组织为板条状回火马氏体。析出相主要由M23C6、Nb(C,N)和极少量的Laves相组成,M23C6析出数量随回火温度升高而增加。经过570、690℃两次回火处理,可提高合金的冲击韧性。     

一种定向凝固镍基铸造高温合金的物理化学相分析

系统研究了一种定向凝固镍基铸造高温合金的物理化学相分析方法。对3种热处理制度下的试验合金中各析出相的结构、化学组成和含量及γ′相+微量相的粒度分布进行了测定,揭示了该合金中析出相在不同状态下的变化规律。该合金的析出相为:γ′,(Ti,Nb)C,HfC,M23C6,W3.2Cr1.8B3,WB,M6C(痕)等,没发现μ和M3B2相析出。粒度分布结果表明,在900℃时效3 000 h,γ′相略有长大。     

25Cr3Mo3NiNb钢的物理化学相分析方法的研究

系统研究了25Cr3Mo3NiNb钢的物理化学相分析方法.对不同回火温度下试验钢中各析出相的结构、化学组成和含量进行了测定,揭示了25Cr3Mo3NiNb钢中各析出相随回火温度的析出规律.随回火温度升高,试验钢中相继析出M3C,M2C,M(CN),M7C3等碳化物.     

建筑用H型耐火钢中析出相的状态分析

采用物理化学相分析、X射线衍射和小角散射以及扫描电镜等多种分析手段对H型耐火钢中化合物的结构、形貌、含量及其颗粒尺寸进行了分析。发现该耐火钢中析出的碳化物主要为M3C、MC和M2C相,同时还存在数量较多的氧化物和硫化物。探讨了耐火钢的不同回火温度对其析出的化合物的影响规律,发现回火温度对于M3C相的数量和平均粒径影响较大,MC和M2C相的数量随回火温度的升高而有所增加,而平均粒径无明显变化。硫化物数量基本不随热处理制度变化。     

含Cr油罐钢的碳化物析出研究

研究了油罐用含Cr低碳合金钢在950℃淬火+650℃回火以及不同保温时间条件下Cr的碳化物析出,从而解释了不同调质工艺性能的变化。Cr在回火后容易形成M7C3及M23C6碳化物,这两种碳化物处于亚稳状态,随回火时间延长容易聚集长大,并且形态呈现长条状。对不同回火保温时间下含Cr钢第二相粒子析出行为的研究发现,在1 min/mm的保温时间下,没有发现含Cr的碳化物析出;随着保温时间的增加,Cr的碳化物快速析出并迅速长大;在3 min/mm的保温时间下,含Cr的碳化物尺寸达到300 nm。因此,低碳调质高强度合金钢生产必须采用合适的调质工艺,适当缩短回火保温时间,才能避免Cr的碳化物聚集长大引起的强度及塑性降低。     

SA508-3 钢平衡相转变的热力学计算和分析

采用Thermo-Calc热力学软件计算了SA508-3钢(％:0．19C、0．01-0．22Si、1．40-1．58Mn、0．65- 0．76Ni、0．50-0．55Mo)的析出相、析出温度和各相的含量,并研究了Si和Mn-Ni-Mo含量对该钢析出相的影响。计算结果表明,SA508-3钢平衡态的析出相主要为合金渗碳体、M7C3及Mo的碳化物。Si含量变化对钢中各相析出温度和析出量无显著影响。随Mo含量降低,钢中脆性相析出减少,但对合金渗碳体析出无显著影响。SA508-3钢最佳回火温度为643-678℃。     

Ti-Mo微合金钢回火过程中纳米碳化物析出行为

利用透射电镜对含Ti微合金钢热轧及回火后的析出相分布、形貌和尺寸进行了观察和分析,结合拉伸试验结果研究了回火过程中纳米析出颗粒的变化特征及其对试验钢强度变化的影响。结果表明,600℃回火2 h试验钢的屈服强度达到最大值,这是由于除了热轧后空冷形成的高体积分数相间析出以外,回火过程中又形成了大量的过饱和析出,此时纳米析出相体积分数较其他温度增加约3%～5%,颗粒平均尺寸为5～6 nm,分布最均匀。随着回火温度的升高和回火时间的延长,2类析出颗粒均发生了不同程度的粗化,相间析出颗粒尺寸均在8 nm以下,较过饱和析出颗粒具有较好的热稳定性,析出强化作用更明显。     

Inconel 690合金TT处理后的析出相

 用扫描电子显微镜、透射电子显微镜和相分析研究了3种不同钛含量的Inconel 690合金经不同固溶温度+715 ℃×15 h,TT处理后的析出相。结果表明：合金经TT处理后,均有M23C6析出,并含有一定量的Ti(C,N);钛含量为110%的合金中有γ′相析出,γ′相在晶内弥散分布;M23C6大多在晶界上析出,而且在孪晶界和晶内位错线处也均有析出,M23C6与界面一侧基体保持立方 立方的平行位向关系;钛含量增加,析出的M23C6尺寸变小,间距增大,晶界附近的铬含量明显提高,有利于改善合金的耐腐蚀性能。     

回火温度对中碳合金钢4Cr5MoSiV1Nb组织和性能的影响

 为了优化合金性能，研究了回火温度对中碳合金钢4Cr5MoSiV1Nb组织和性能的影响。试验结果表明，4Cr5MoSiV1Nb合金钢的二次硬化温度区间为300～550 ℃，峰值出现在550 ℃，此时硬度值为56.3HRC，同时伴有冲击韧性的显著降低，冲击韧性降低的原因是合金钢回火时含铬铬的细短棒状合金渗碳体在晶界析出，可以推测减少淬火合金钢中铬的偏析将会减少晶界析出，提高冲击韧性。微量铌的加入形成了（V，Nb）C强化相颗粒。合金在250～350 ℃回火综合性能最佳，可以达到冲击韧性15 J/cm2、硬度55HRC以上。     

X80管线钢中Nb元素析出规律的研究

采用热力学模型计算了X80管线钢在不同温度下的相组成,相析出温度及Nb元素的析出规律;研究不同Nb含量对A3温度、各相析出温度和Nb析出规律的影响。计算结果表明,X80管线钢平衡态的析出相主要为Ti,Nb的碳氮化物、合金渗碳体、MnS、AlN、M7C3和Mo的碳化物。随Nb含量的增加,A3温度升高,Nb析出相的析出温度升高,而AlN相析出温度降低;在同一温度下Nb元素的析出量随Nb含量增加而升高。     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

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)     

Comparison of rates of infection of two methods of emergency ventricular drainage

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.     

浅析《野草》的版画特征

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".     

四辊破碎机车刀架的改造

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。     

转炉炉壳热应力分析

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。     

Comparison of the results of surgical and conservative treatment of fractures of the diaphysis of the tibia

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.     

焦炭热性能指标意义浅析

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。     

Results of treatment of cancer of the cardia

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.     

参与式农业基地建设行动方案设计

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.