搜索结果: 16-30 共查到“知识库 材料失效与保护”相关记录2038条 . 查询时间(3.703 秒)
在对带有一个铆接孔的试件进行试验研究的基础上,利用性能退化失效曲线,提出了一种新的初始疲劳质量和裂纹扩展速率的确定方法.根据试验结果和理论推导,建立了裂纹扩展长度与加载循环次数的函数关系.在此基础上,估算了EIFS值,并用指数函数拟合方法估计了疲劳裂纹扩展速率.最后通过对临界裂纹尺寸的理论计算验证了新方法的可行性和有效性.
显微组织对X80钢氢致裂纹敏感性及氢捕获效率的影响
材料腐蚀与防护 管线钢 氢致裂纹（HIC）敏感性 渗氢曲线 焊接热影响区
2010/8/10
本文采用针状铁素体为主的X80管线钢，通过不同的热处理工艺得到X80管线钢多边形铁素体组织试样和板条马氏体组织试样。分别测试三种组织试样在饱和H2S环境中的氢致裂纹（HIC）敏感性及氢渗透行为。结果表明：不同组织X80钢的HIC敏感性大小次序为：水淬处理的板条马氏体组织试样>空冷处理的多边形铁素体组织试样>原始针状铁素体组织试样；氢在材料中的捕获效率是影响材料HIC敏感性的主要因素之一，渗氢通量J...
根据对现有的压力容器、石油管道腐蚀失效案例和现有失效知识的分析与总结，提出了晶间腐蚀和氢致开裂两种模式的腐蚀失效特征。依据这些失效特征建立相应的两种腐蚀失效模式的失效判断规则，根据这些失效规则运用COM Wizard、数据库技术和可靠性技术建立有效的腐蚀失效模式诊断专家系统。该专家系统根据输入的腐蚀失效特征来识别案例的腐蚀失效模式并给出综合可信度作为诊断结果的评价参数。
Comparison of surface laser alloying of chosen tool steel using Al2O3 and ZrO2 powder
Comparison alloying tool steel Al2O3 ZrO2 powder
2010/3/12
In this paper there is presented the laser treatment as a part technology applied for steel surface manufacturing. There is presented laser treatment with remelting of hot work tool steel 32CrMoV12-28...
NO2-和Cl-对模拟混凝土孔隙液中钢筋腐蚀行为的影响
钢筋 模拟混凝土孔隙液
2010/1/18
应用极化曲线法和电化学阻抗技术研究了NO2-和Cl-对钢筋在不同pH值的模拟混凝土孔隙液中的腐蚀行为. 结果表明, 钢筋耐蚀 性与溶液的pH值, 以及NO2-和Cl-的浓度相关. pH值的降低和Cl-浓度的增高都会使钢筋的耐蚀性降低. 在含Cl-的模拟液中, 随着NO2-浓度升高, 钢筋腐蚀速率降低, 在pH值为12.50和10.50的溶液中, 当[NO2-/Cl-]≥0.4时,NO2-对钢筋具有...
Experimental investigation of effects of external loads on erosive wear
Erosive wear Yield strength Impingement angle
2009/12/14
Purpose: The purpose of the paper is to investigate effects of external loads on erosive wear.
Design/methodology/approach: In this experimental study, specimens were placed on specially designed a s...
Pitting corrosion in the wet section of the automotive exhaust systems
Metallic alloys Pitting corrosion Evaluation methods for pitting corrosion
2009/12/14
Purpose: In the rear section of the automotive exhaust systems condensates bearing appreciable chloride ion concentrations and often low pH-values together with particles of electrochemical active soo...
FEM modelling of internal stresses in PVD coated FGM
Computational materials science Finite Element Method Stresses
2009/12/14
Purpose: The general topic of this paper is problem of determining the internal stresses of composite gradient tool materials with the use of finite element method (FEM). The chemical composition of t...
Purpose: of the paper was comparison of the structure, adhesion and wear resistance of the monolayers CrN and TiN PVD coatings deposited onto plasma nitrited X37CrMoV5-1 type hot work tool steel.
Des...
Forecasting of durability of waterborne coatings in the machine industry
Mechanical properties Forecast Durability
2009/12/3
Purpose: The paper presents the problems of forecasting of durability of waterborne acrylic coatings and epoxy coatings designed to protect devices and machine elements.
Design/methodology/approach: ...
Criteria of assessment of powders provided to spray by the APS method for new and conventional layers type TBC
Metallic alloys Thin&thick coatings TBC
2009/12/3
Purpose: Verification of up-to-now use of conventional powders, provided to spray by the APS method for layers type TBC and its possible adaptation to layers of new types, which are based on new ceram...
Creep damage mechanisms in gas pipes made of high density polyethylene
Engineering polymers Creep-resistance Mechanical properties
2009/12/3
Purpose: The purpose of this article is to present results of creep damage mechanisms in gas pipes made of high density polyethylene [HDPE]. High density polyethylene has been widely used in the pipin...
Hard gradient (Ti,Al,Si)N coating deposited on composite tool materials
Gradient coatings XPS PVD
2009/12/3
Purpose: This paper presents investigation of gradient coating of (Ti,Al,Si)N deposited on the Al2O3+SiC(w)
oxide ceramics substrate deposited with the PVD process.
Design/methodology/approach: Stru...
Optimizsation of the lacquering process
Optimisation Multiobjective optimisation Industrial management
2009/12/2
Purpose: The topic of this research is estimation of coat parameters generate by paint robots. The purpose of this article is to present results of optimization of the varnishing process.
Design/meth...
Purpose: The X-Ray Photoelectron Spectrometry (XPS) and Auger Electrons Spectroscopy (AES) analysis of PVD
coatings were performed for samples, made from cemented carbides, cermets and composite grad...