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1.
热处理对工模具钢5Cr8MoVSi组织及硬度的影响   总被引:1,自引:0,他引:1  
工模具钢5Cr8MoVSi(0.55C,8.13Cr,1.38Mo,0.45V,0.72Si)经840℃退火硬度为HB218,钢中碳化物以M23C6为主,并有少量的MC和M7C3。该钢合适的淬火温度为980—1050℃,最高硬度为HRC60—61。随淬火温度升高,淬火马氏体由板条状和针状马氏体组织过渡到板条状马氏体组织,剩余碳化物主要为MC和M7C3,为减少残余奥氏体量,该钢应进行二次或三次回火。  相似文献   

2.
适当提高淬火温度,由于未溶碳化物(M23C6)的减少可使韧性得到改善,16NiCo(0.16C-10Ni-14Co-1Cr-1Mo)钢的淬火温度超过860℃,510℃回火的冲击韧性和断裂韧性将出现缓慢下降。23NiCo(0.23C-12Ni-14Co-3Cr-1Mo)钢的淬火温度超过950℃,482℃回火冲击韧性大幅度降低。  相似文献   

3.
试验研究了经不同温度正火和回火后,0.14C—1.25Cr—0.5Mo钢中M3C、M23C6碳化物中Cr、Mn、Mo的含量以及充氢前后淬火和回火温度对钢的力学性能的影响。结果得出,经890-980℃正火、670-710℃回火,该钢具有良好的抗氢蚀能力,520~620℃回火后试样充氢后的强度明显下降。  相似文献   

4.
吴华杰  傅杰  刘阳春 《特殊钢》2006,27(4):19-21
用化学相分析加X-射线小角散射法对微合金高强度钢70A(%:0.05C,1.90Mn,0.01V,0.13Ti, 0.06Nb)和B2C(%:0.06C,2.34Mn,0.03V,0.03Ti,0.04Nb,0.0067B)的析出相结构、质量分数和粒度分布进行了研究。结果发现,微合金化钢亦存在大量纳米级M3C和M23C6碳化物,70A钢中<36 nm的M3C+M23C6碳化物质量分数为0.0664%,同尺寸的MC碳化物为0.0371%;B2C钢中<36 nm的M3C+M23C6碳化物的质量分数为0.134 1%,同尺寸的MC为0.008 4%。  相似文献   

5.
高速钢粉末真空高温处理时组织结构之变化   总被引:1,自引:0,他引:1  
研究了水雾化M 2和M 4高速钢粉末在 7× 10 -2 Pa真空下加热后组织结构的变化。当粉末加热至固相线以下 15~ 2 0℃ ,即 12 2 0~ 12 2 5℃时 ,M6C及MC型碳化物都由 1~ 2 μm长大到 3~ 4 μm ;当粉末加热至固相线以上时 ,碳化物尤其是M6C型碳化物颗粒快速长大 ,并且有不均匀长大现象 ;当温度升至 12 5 0℃后 ,贫碳型的M4C3 转变为MC型碳化物 ,其中大部分Fe被V所取代 ;当进一步加热至 12 6 0℃以上时 ,M6C型碳化物将转变为M2 C碳化物。经真空脱氧后高速钢粉末的氧含量降低至 10 0× 10 -6以下。  相似文献   

6.
宋义全 《特殊钢》2001,22(5):16-18
0.1C-1.5Si-1.5Mn-0.4Cr钢获得了0.06C-1.3Si-0.9Mm-0.4Cr-0.35Mo型热轧双相钢(F+M)的相变动力学,即在CCT曲线上出现了温度间隔为100℃的奥氏体亚稳区。随冷速的降低,Si-Mn-Cr钢的组织中多边形铁素体量增多,贝氏体量减少,当冷速减小到0.5℃/s时,组织中出现针状马氏体。  相似文献   

7.
刘德富  尹钟大  徐德祥  高峰  李朝华  赵晗 《钢铁》2005,40(4):69-71,82
采用X射线衍射分析、TEM组织观察和电子衍射分析,对新型半高速钢在加热和冷却及回火过程中碳化物的溶解和析出行为进行了研究。结果表明,退火状态下钢中含有MC、M6C和M7C3型碳化物;淬火加热时M6C和M7C3型碳化物全部溶解,回火过程中析出MC、M2C、M6C和M7C3型碳化物,当回火温度为520℃时出现硬度峰值,此时Mo2C的弥散强化起主要作用。  相似文献   

8.
研究了0—1.5%Nb对25kg真空感应炉冶炼的W3M02Cr4V钢(%:0.8~1.1C、3.8~4.1Cr、2.9-3.2W、1.8-2.1Mo、1.0-1.3V)组织和力学性能的影响。试验结果表明:随着Nb含量提高,铸态组织中铌碳化物增多;淬火奥氏体晶粒变细;1180℃淬火时,1.2%-1.5%Nb钢比≤0.1%Nb钢HRC值提高了6.0;二次硬化能力和红硬性也得到了提高;使钢在较高淬火温度下的机械性能得到改善。  相似文献   

9.
4Cr14Ni14W2Mo耐热钢的热力学分析与改性研究   总被引:1,自引:0,他引:1  
周悠  宛农 《特钢技术》2006,11(4):1-4
为研究碳化物的类型、数量和分布对4Cr14Ni14W2Mo耐热钢使用性能的影响,采用Thermo—Cale软件分析了该钢在不同温度下各平衡相数量、组成与钢中W、Mo含量之间的定量关系。计算结果表明,此钢中的碳化物在1135℃几乎完全固溶,在750℃时效析出量选最大;适当提高W、Mo含量,即当Mo(%)+0.7W(%)≥5.0时,可使钢在时效处理后其晶界上形成颗粒状M6C碳化物,减少沿晶界析出的M23C6碳化物,从而就能减少渗氮层剥落倾向。上述分析鲒果与前人所得的经验数据基本吻合,为该钢的改性起一定的理论指导作用。  相似文献   

10.
新型不锈轴承钢6Cr14Mo冲击韧性与显微亚结构   总被引:1,自引:0,他引:1  
在同等硬度下,新型不锈轴承钢6Cr14Mo(%:0.64C,13.6Cr,0.62Mo)的冲击韧性ak比9Cr18不锈轴承钢(%:0.94C,18.6Cr)高14—30J/cm^2。从碳化物电镜复型分析可见,6Cr14Mo钢淬、回火组织中主要为细小、弥散分布的二次碳化物,一次碳化物较少,而9Cr18钢组织中一次碳化物较多。新型不锈轴承钢6Cr14Mo的基体组织为板条马氏体,并有少量残余奥氏体,组织中的碳化物主要为M23C6以及弥散析出的Mo2C和ε-Fe2C。  相似文献   

11.
12.
根据深云立交桥梁的检测结果,对该桥目前的整体状况、工作状态,及其使用情况做出综合评价,对桥的病害原因进行了分析,并提出合理的加固方案。  相似文献   

13.
劳伦斯小说《儿子与情人》一个鲜明的语言特色就是标准英语和当地方言频繁的语码转换。莫瑞尔用方言来对抗妻子,而妻子坚持用标准英语,偶尔也用方言来讽刺、挖苦丈夫。语码转换反映了劳伦斯男女二元对立的哲学思想。  相似文献   

14.
Social comparison involves positioning the self relative to others on a vertical or status dimension (ranging from upward to downward comparisons) and a horizontal or solidarity dimension (ranging from contrastive to connective comparisons). Across 3 studies in which 389 undergraduates recorded everyday social comparisons (n = 4,417), downward and connective comparisons were rated as more helpful and mood enhancing than upward and contrastive comparisons. The effects of horizontal comparisons were greater for people for whom solidarity was an important value; however, the effects of vertical comparisons were not greater for people who valued status. The roles of the comparison target, topic, and situation were also explored; for example, noticing undesirable features of the target enhanced status but undermined solidarity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
摘要:在第4次工业革命浪潮的推动下,钢铁科学与技术正在经历数字化、智能化转型。钢铁行业全流程各工序均为“黑箱”,为多场、多相、多变的巨系统,具有复杂相关关系和遗传效应等。这些不确定性带来了巨大的挑战。挑战和机遇并存。这些不确定性提供了智能化和数字化技术的应用场景资源;钢铁行业极为丰富的大数据提供了挖掘其中蕴含客观规律的数据资源;现代的数据科学、智能技术为解决不确定性问题提供了强大的手段。以数据为中心,以工业互联网为载体,以实验工具、数字数据、计算工具为支撑,建设钢铁企业材料创新基础设施,将可以大幅度提高研发效率,降低研发成本,有力地支撑钢铁材料科学与技术的转型发展。实验工具平台除了传统的实验室仪器装备和中试装备之外,实际生产线被作为主要的实验工具。这些实验工具提供丰富、精准、写实的历史数据和现实生产数据,特别是生产线装备提供实际生产大数据,蕴含着生产过程中的全部规律,是极宝贵的数据资源。利用机器学习、深度学习等现代数据挖掘技术为计算工具,对这些数据资源进行处理、分析、计算,将数据转换为高保真度模型,可以得到具有“原位分析能力”的数字孪生。在工业互联网的总体架构下,以数字孪生为核心,组成信息物理系统,构建起基于数据自动流动的状态感知、实时分析、科学决策、精准执行的闭环赋能体系,解决生产制造、应用服务过程中的复杂性和不确定性问题,提高资源配置效率,实现资源优化,对材料行业转型发展提供关键技术支撑。虚实映射、实时交互、精准控制的信息物理系统与材料创新基础设施合二为一,以材料创新基础设施为基盘,形成具有“原位分析能力”的数字孪生,建设钢铁生产全流程、一体化的信息物理系统,必将推进钢铁行业智能制造蓬勃开展和数字化、智能化转型。  相似文献   

16.
Two studies investigated the role of expressive vocal behavior (specifically, speech rate and loudness) in fear and anxiety and in sadness and depression. In the 1st study, participants spoke about personally experienced fear and anxiety-arousing and neutral events using 3 different voice styles: fast and loud, normal, and slow and soft. In the 2nd study, participants spoke about personally experienced sad or depressing and neutral events using the same 3 voice styles. In both studies, the participants' highest levels of subjective affective and cardiovascular (CV) arousal occurred when they spoke about the emotional events in a mood-congruent voice style: fast and loud in the case of fear and anxiety, and slow and soft in the case of sadness or depression. Mood-incongruent voice styles canceled the heightened levels of CV arousal normally associated with these negative emotions. The voice-style manipulation had no significant effect on the participants' levels of CV arousal during the neutral discussions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

17.
Daniel Robinson suggests that much of the civil and criminal law "serves as the institutionalized form of praise and blame". Indeed it does. Pulling at this thread of Robinson's tapestry leads the reader straightaway to a host of truths about how law and morality not only intersect, but work together in harmony. "[L]aw", Robinson says, is a "vivid expression of deeper and impenetrably complex moral theories". This essay explores several of these harmonies, but focuses on two. One is that political society must be seen as the cooperation of free persons according to law, which persons hold common moral understandings. The second has to do with retribution as the moral justifying aim of punishing criminals. The author goes beyond Robinson's limited praise of retribution, and shows that some central features of our practice of punishment are understandable only within the retributive framework. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
为解决单个企业的信息化投资风险、从整体上降低企业信息化投入,针对大邱庄钢铁产业的类型特点,设计了一种新型信息化公共服务平台。详细阐述了钢铁产品展示及交易平台的建设内容及系统开发技术。该平台集产品展示、信息查询、用户管理功能于一体,实现了全自动、全智能的在线管理和维护,适用于中小型企业。该平台的应用最大化地发挥了大邱庄的产业优势,对大邱庄工业园区的宣传和市场开拓起到了一定的作用。  相似文献   

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20.
The relationship between aging and negative affect is dynamic and complex. Although prior studies have often cited lower prevalence rates of anxiety and mood disorders among older individuals, these studies may miss the dynamic relationship between symptoms and aging. To evaluate a nonlinear model of the relationship between aging and negative affect, the author examined measures of neuroticism, anxiety, and depression symptoms in a cross-sectional, community sample (N = 335), ages 18 to 93. Results indicated a curvilinear relationship, with mean symptom levels increasing during early adulthood (until the mid-30s) and then showing a small decline until older adulthood (the mid-70s), when symptoms again increase with age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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