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1.
代位原子在Fe3Al亚点阵中的占位与合金的塑性   总被引:2,自引:0,他引:2  
采用中子衍射法测定了Cr、Mo、Ti、Ni、Mn、Si等代位原子在DO3结构Fe3Al亚点阵中的原子占位,并从解离能角度探讨了原子对之间的相互作用及合金室温塑性的影响,结果表明:Cr、MO、Ti都占据了Al原子的次近邻位置,替代Fe原子;Ni、Mn占据Al原子的最近邻位置,(Si+A)当量成分以内的Si原子替代占据Al原子的位置,由于Al-Cr原子对的结合能低于Fe-Al,AL-Mo用Al-Ti对  相似文献   

2.
通过控制化学成分和处理工艺,得到一种弥散无序γ相强化的Ni_3Al基合金。TEM分析发现:弥散无序的γ相是在有序γ'基体{001}面上析出的,且与基体保持共格关系。在不同温度下对该合金进行拉伸试验发现:弥散γ相的强化作用,使M_3Al基合金拉伸屈服强度的峰值温度升高到850℃左右;与相同处理条件下成分相近的IC218合金相比较,该合金的高温屈服强度和拉伸强度以及峰值温度以下的形变硬化率都发生显著的提高。文中在SEM下对拉伸试样的断口特征进行了分析,并对无序γ相的弥散强化机理进行了探讨。  相似文献   

3.
通过控制化学成分和处理工艺,得到一种弥散无序γ相强化的Ni_3Al基合金。TEM分析发现:弥散无序的γ相是在有序γ'基体{001}面上析出的,且与基体保持共格关系。在不同温度下对该合金进行拉伸试验发现:弥散γ相的强化作用,使M_3Al基合金拉伸屈服强度的峰值温度升高到850℃左右;与相同处理条件下成分相近的IC218合金相比较,该合金的高温屈服强度和拉伸强度以及峰值温度以下的形变硬化率都发生显著的提高。文中在SEM下对拉伸试样的断口特征进行了分析,并对无序γ相的弥散强化机理进行了探讨。  相似文献   

4.
研究了微量V对DO3型Fe3Al基合金伸性能和组织结构的影响。结果表明,V可细化晶粒,改善Fe3Al合金室温强度和塑性,室温伸断口也由穿晶解理型转变为加沿晶混合型,V还使Fe3Al合金高温强度峰值对应的温度提高约200℃,从而提高Fe3Al合金高温强度峰值对应用温度提高约200℃,从而提高Fe3Al合金使用温度。  相似文献   

5.
助烧剂对热压Si3N4基陶瓷组织结构的影响   总被引:1,自引:0,他引:1  
用XRD,SEM,TEM分析了用Y2O3+Al2O3及Y2O3+AlN做助烧剂的两种热压Si3N4基陶瓷的组织结构,用EDXA分析了Si,Al,Y等元素的含量。结果表明,两种Si3N4都是由长柱状β相组成;  相似文献   

6.
安白  马莒生 《功能材料》1995,26(5):461-464
用TEM、X-Ray、SEM等技术研究了Ni42Cr6Fe玻封合金在高温湿H2中形成的氧化膜及氧化物晶须的结构。结果表明:氧化膜主要由Cr2O3和(Fe,Mn)Cr2O4两组相成,氧化膜底层是以Cr2O3为主的组织,氧化膜表层是以(Fe,Mn)Cr2O4为主的组织;Si在氧化膜与合金界面分布,Al则在内氧化层中形成内氧化物质点;氧化膜表面生长的氧化物晶须的杆部为(Fe,Mn)Cr2O4单晶,头部为  相似文献   

7.
低密阻尼金属/金属复合体材料的组织与性能研究   总被引:4,自引:1,他引:3  
采用快速凝固/粉末冶金法成功地研制出Al-7.09%Fe-1.34%Mo-1.45%Si(FMS0714)合金及其金属/金属复合体材料FMS0714/15%Al和FMS0714/10%(Zn-30%Al),考察了其组织、拉伸性能、阻尼性能和密度,产散锻铝LD7CS合金进行了对比。结果表明:FMS0714合金本身就具有较好的拉伸与阻尼性能。添加纯Al和Zn-30%Al合金粉均使其强度下降,而 FMW  相似文献   

8.
(Ni,Fe)Al金属间化合物的快速凝固组织与室温塑性   总被引:1,自引:0,他引:1  
用单辊快速凝固法制备(NiFe)Al金属间化合物并研究其组织与室温塑性。结果表明,Al-45Ni-5Fe(原子分散)在快速凝固条件下可形成内部为亚微米级针状亚晶的等轴晶粒,具有高达3.1%的弯曲塑性,Al-35Ni-15Fe和Al-25Ni-25Fe的快凝组织则为柱状晶,弯曲塑性仅有1.1%1.0%,针状亚晶是一定成分的(Ni,Fe)Al在快速凝固条件下形成的亚稳相,其形成机制和快速凝固过程中原子  相似文献   

9.
研究了2at%Ti元素对B2结构Fe-36.5at%Al金属间化合物组织和从室温至高温拉伸性能的影响。结果表明,Ti元素完全面溶于FeAl合金,使FeAl合金高温性能有所提高,同时亦提高低温强度和中温塑性,对低温塑性没有改善。Ti不改变FeAl合金的变形机理,亦不改变合金断裂模式,仅使700℃以下温度时混合断口形貌中沿晶断裂部分所占比例增加。  相似文献   

10.
用Mossbauer谱学和XRD方法研究了快速凝固Al-5Fe-2Ni(原子百分数)合金的析出相,结果表明,析出相为三元化合物Al9FexNi2-x(0〈x〈2)属于单斜晶系,晶格参数a=0.858nm,b=0.631nm,c=0.621nm,β=94.8,它的Mossbauer谱为一套双线,同质异能移位IS=0.12mm.s^-1,四极分别QS=0.32mm.s^-1,线宽Г=0.26mm.s^  相似文献   

11.
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.  相似文献   

12.
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……  相似文献   

13.
14.
We associate a variety of innovations with the term "Industry 4.0". The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...  相似文献   

15.
A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.  相似文献   

16.
On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……  相似文献   

17.
ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.  相似文献   

18.
Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.  相似文献   

19.
In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M2(B,C), (W,Mo)2(B,C), M3(B,C), M23(B,C)6 type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm2. The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K1 mill housing of bar mill.  相似文献   

20.
正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from  相似文献   

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