Three-dimensional Modeling of Ore-forming Elements and Mineralization Prognosis for the Yechangping Mo Deposit,Henan Province,China

Three-dimensional geochemical modeling of ore-forming elements is crucial for predicting deep mineralization.This approach provides key information for the quantitative prediction of deep mineral localization,three-dimensional fine interpolation,analysis of spatial distribution patterns,and extraction of quantitative mineral-seeking markers.The Yechangping molybdenum(Mo)deposit is a significant and extensive porphyry-skarn deposit in the East Qinling-Dabie Mo polymetallic metallogenic belt at the southern margin of the North China Block.Abundant borehole data on oreforming elements underpin deep geochemical predictions.The methodology includes the following steps:(1)Threedimensional geological modeling of the deposit was established.(2)Correlation,cluster,and factor analyses post delineation of mineralization stages and determination of mineral generation sequence to identify(Cu,Pb,Zn,Ag)and(Mo,W,mfe)assemblages.(3)A three-dimensional geochemical block model was constructed for Mo,W,mfe,Cu,Zn,Pb,and Ag using the ordinary kriging method,and the variational function was developed.(4)Spatial distribution and enrichment characteristics analysis of ore-forming elements are performed to extract geological information,employing the variogram and w(Cu+Pb+Zn+Ag)/w(Mo+W)as predictive indicators.(5)Identifying the western,northwestern,and southwestern areas of the mine with limited mineralization potential,contrasted by the northeastern and southeastern areas favorable for mineral exploration.

Effect of Mn and Mo on microstructure and mechanical properties of Al-Si-Cu-Mg-0.6Fe alloy

Effect of different Mn and Mo contents on microstructure and mechanical properties of Al-Si-Cu-Mg-0.6Fe alloy was studied.Results indicate that the increase of Mo and decrease of Mn lead to a decrease in the size of theα-Al_(15)(FeMnMo)_(3)Si_(2) phase formed during solidification.Theα-Al_(15)(FeMnMo)_(3)Si_(2) phase reaches a minimum value of about 16.3μm at 0.2wt.%Mo and 0.1wt.%Mn addition.After solution treatment,theα-Al(FeMnMo)Si dispersed phase is precipitated.When only Mn is added,theα-Al(FeMnMo)Si dispersed phase mainly distributes near the grain boundaries,while when only Mo is added,it primarily distributes in the central region of the matrix.When both Mn and Mo are added,the dispersed phase has a larger and denser dispersed region and is uniformly distributed near the Al matrix and grain boundaries.Moreover,the best overall mechanical properties of the alloy are obtained with the combined addition of 0.1wt.%Mn and 0.2wt.%Mo,due to the smaller size ofα-Al_(15)(FeMnMo)_(3)Si_(2) phase and the larger area fraction and higher density of theα-Al(FeMnMo)Si dispersed phase.The yield strength,ultimate tensile strength,and elongation are respectively improved 67.7 MPa,48.5 MPa and 5.3%,respectively,compared to that of the alloy with only 0.3wt.%Mn.

基于Mn-MOF制备MeO_(x)/MnO_(x)催化剂的低温NH_(3)-SCR活性研究

采用不同金属硝酸盐浸渍Mn-MOF前体制备一系列MeO_(x)/MnO_(x)(Me=Co,Cr)复合金属氧化物催化剂用于低温NH3-SCR反应。分析金属掺杂和空速对锰基催化剂脱硝效率和N_(2)O生成量的影响。通过XRD、SEM、N2吸附-脱附、XPS、H_(2)-TPR、NH3-TPD等表征测试对制得的催化剂物理化学性质进行分析,结果表明,两种金属掺杂可不同程度上改善MnO_(x)脱硝性能和抗硫性能。与MnO_(x)催化剂相比,掺杂催化剂的外观呈现无规则的多孔结构。更大的比表面积为活性分子提供更多的活性位点,有利于脱硝反应进行。掺杂催化剂中Mn元素相以Mn_(3)O_(4)相为主,且峰强度较低,表明Mn元素相呈现高分散态。掺杂金属与锰氧化物产生相互作用,改变了锰元素的价态,提高了Mn^(4+)和表面氧的含量。金属离子掺杂增强了催化剂的氧化还原性能,改善了MnO_(x)的表面活性。因此,金属硝酸盐浸渍Mn-MOF前体法在制备低温NH3-SCR脱硝催化剂领域具有很好的应用前景。

回火温度对Mn-Cr-Ni-Mo钢调质后组织与性能的影响

以Mn-Cr-Ni-Mo低碳低合金钢为研究对象,在JMatPro软件模拟的基础上,采取组织分析与性能测试等方法研究了不同回火温度条件下的组织与性能。结果表明:试验钢经淬火后的显微组织为板条贝氏体+多边形块状铁素体+马氏体,再经600~700℃高温回火时,随着回火温度的提高,马氏体和贝氏体先后逐渐转变,碳化物析出量提升,出现晶粒细化现象,平均晶粒度提高,这些组织变化导致材料强度和硬度降低而冲击韧性上升。在640℃回火时出现二次硬化现象,导致强度有所提高,冲击韧性相对略有下降,且在0~-40℃时的冲击值无明显变化,保持较高的强-韧性匹配。Mn-Cr-Ni-Mo低碳低合金钢采用910℃淬火+640℃回火的热处理工艺方案可行,能满足试验钢生产X60、X65和X70等钢级管线管的技术要求。这种用单一钢种生产多个不同钢级的钢管是保障生产管理、降低成本和提升效益的重要途径,有助于提升管线管产品的市场竞争力。

EFFECTS OF RARE EARTH ELEMENTS ON THE CHARACTERISTICS OF AUTO-TEMPERING AND DECOMPOSITION OF MARTENSITE FOR A LOW CARBON Si-Mn-V STEELS

The effect of rare earth metals(REM)on the characteristics of auto-tempering and decomposition of martensite for low-carbon and low-alloy steels(20SiMn2V and 20SiMn2VRE)was investigated using TEM,dilatometer and microhardness test.Results show that both ε.and θ carbides,during auto-tempering, may precipitate from the low-carbon martensite matrix at the same time in the 20SiMn2V steel,however,the precipitation of the ε-carbides can be inhibited by the REM contained in the 20SiMn2 VRE steel,resulting in change of the type of precipitated carbides and decrease of the extent of auto-tempering.The“in-situ”ob- servations show that the decomposition of martensite is also inhibited by the REM contained in the 20SiMn2 VRE steel during low temperature tempering.

核电容器用Mn-Ni-Mo钢大锻件的热处理

Mn-Ni-Mo钢具有良好的焊接性能、较好的强韧性和抗中子辐照脆化性能,常用于制作压水堆核电容器用大锻件。但Mn-Ni-Mo钢的淬透性中等,先进核电容器用Mn-Ni-Mo钢大锻件难以通过常规热处理获得所需要的高性能。2000年以来,上海电气上重铸锻有限公司(简称上重)联合上海交通大学在材料特性、热处理工艺和淬火装置等方面进行了试验研究,结果显著提升了核电容器用Mn-Ni-Mo钢大锻件的热处理技术水平,上重制造的核电容器用大锻件性能达到了国际先进水平。

Effect of Mn Promoter on Structure and Performance of K-Co-Mo Catalyst for Synthesis of Higher Alcohols from CO Hydrogenation

A series of Mn-doped K-Co-Mo catalysts were prepared by a sol-gel method. The catalyst structure was well characterized by X-ray diffraction, N2 physisorption, NH3 temperature- programmed adsorption, in situ diffuse reflectance infrared Fourier transform spectroscopy, and X-ray absorption fine structure spectroscopy. The catalytic performance for higher alcohol synthesis from syngas was measured. It was found that the Mn-doped catalysts ex- hibited a much higher activity as compared to the unpromoted catalyst, and in particular the C2＋ alcohol selectivity increased significantly. The distribution of alcohol products de- viated from the Anderson-Schulz-Flory law. The portion of methanol in total alcohol was suppressed remarkably and the ethanol became the predominant product. Characterization results indicated that the incorporation of Mn enhanced the interaction of Co and Mo and thus led to the formation of Co-Mo-O species, which was regarded as the active site for the alcohol synthesis. Secondly, the presence of Mn reduced the amount of strong acid sites significantly and meanwhile promoted the formation of weak acid sites, which had a positive effect on the synthesis of alcohol. Furthermore, it was found that the incorporation of Mn can enhance the adsorption of linear- and bridge-type CO significantly, which contributed to the formation of alcohol and growth of carbon chain and thus increased the selectivity to C2＋OH.

高强无磁不锈钢Cr21Ni13Mn5Mo2N的热加工特性

利用Gleeble 3800热模拟机对奥氏体不锈钢Cr21Ni13Mn5Mo2N进行热压缩实验,研究该钢种的高温变形与应变速率以及温度的关系,建立了双曲正弦本构方程,最终得到其热激活能为679.58 kJ/mol,应变速率因子Z=εexp(679580/R T)。实验结果表明,在950~1200℃,0.01~10 s^(-1)条件内,材料变形过程均发生动态再结晶,在950℃,应变速率为0.1 s^(-1)条件下,再结晶开始的变形量为10%。流变应力随温度升高及应变速率降低呈现明显下降趋势,由950℃、10 s^(-1)时的326 MPa降低至1200℃、0.01 s^(-1)时的75 MPa。结合微观组织分析及锻造试验,对压缩试样开裂问题进行深入探究,结果表明晶界处碳、氧化物的聚集恶化晶界塑性,导致热变形过程中在该处形成裂纹源并逐步扩展。通过热处理和热变形试验,确定Cr21Ni13Mn5Mo2N电渣锭在1170℃固溶6 h后晶界碳、氧化物消除,电渣锭晶界处结合力明显提升,成功消除锻造开裂问题,实现锻造成材率大幅提升。

热处理工艺对高强度Mn-Mo-Ni核电钢板组织和NDT温度的影响

通过高倍显微镜、扫描电镜,对30 mm、90 mm厚度高强度Mn-Mo-Ni核电用钢板在不同热处理状态下的组织和断裂韧性展开研究,并依据ASTM E208-95a(R2000)标准分别测定了30 mm厚度钢板表面、90 mm厚度钢板厚度1/4处在不同热处理状态下的无塑性转变(NDT)温度,对比分析试验钢板NDT温度产生差异的原因。结果表明:淬火+回火工艺生产的钢板相比于正火+回火工艺生产的钢板,其NDT温度明显降低;不同淬火+回火工艺生产的钢板,其板厚1/4处NDT温度也存在差异。

Effect of Al in Ti－microalloyed Mn－Ni－Mo welding wire on microstructure and toughness of deposited metal

The effect of Al in Ti-microalloyed welding wire on microstructure and toughness of deposited metals is studied.The results show that the deposited metal toughness worsens with increasing Al in wire' The mechanism of Al is as follows:(1) Al makes oxygen content in deposited metal increase.(2)Al restrains the formation of Ti-rich oxide inclusion, which causes granular bainite microstructure in deposited metal.(3)The content of solute Ti in deposited metal increases with Al content in welding wire,as a result,a part of carbonrich constitution in deposited metal is in the form of twin martensite.

High temperature stress–strain curves of MnS and their applications in finite element simulation

A novel method for testing stress–strain curves of non-metallic materials was presented.The high temperature stress-strain curves of MnS were preliminarily obtained and corrected to account for the influence of friction.Using the finite element method,the influence of deformation parameters on the deformation evolution of MnS inclusions was investigated based on the experimental reference data.The corresponding physical experiment was designed for comparative analysis.The results indicate that the experimental high-temperature deformation data of MnS are highly reliable.In the process of matrix deformation,the shapes of MnS inclusions change from spherical to ellipsoidal and even to lamellar.There are some differences in the morphological deformation of MnS inclusions located at different positions.With the increase in the initial size of MnS inclusions,the risk of failing the inclusion-flaw inspection increases and the forging quality further deteriorates.

Effect of Ageing on Martensitic Transformation and Shape Memory Effect of Fe-Mn-Si-Co-Mo Alloy

This paper discusses the effect of ageing on the thermally induced martensitic transformation and its reverse transformation and shape memory effect of Fe-24Mn-5Si-8Co-4Mo shape memory alloy:the precipitation of Fe 2Mo particles increases the hardness and strength of the alloy as ageing goes on;ageing increases the transformation temperatures;ageing improves,the SME of the alloy so remarkably that a maximum shape recovery ratio is obtained while ageing at 600℃.

Thermal Fatigue Property of Cr-W-Mo-Ni-Mn-RE Ferric-Base Hardfacing Layer

The thermal fatigue property of Cr-W-Mo-Ni-Mn-RE ferric-base hardfacing layer was investigated. The results show that the generation and propagation of thermal fatigue cracks prefer the parts of oxidation and etching of the grain boundary, the joint efforts of cycle stress and oxidation at high temperatures are the main factors in the generation and propagation of thermal fatigue cracks. When the temperatures is below 600 ℃, the Cr-W-Mo-Ni-Mn-RE ferric-base hardfacing layer has higher ability of thermal fatigue resistance. The function of the alloy and rare earth elements was discussed.

Influence of Mn and Mg Contents on Mechanical Properties of the Die-casting Aluminum Alloy HL-111

In this study,four groups of thin plate samples with a wall thickness of 2.2mm,2.5mm,2.7mm,and 3.0mm are prepared by ultra-high vacuum die casting.The effects of Mn,Mg,and Mn/Mg ratio on the microstructure and mechanical properties of samples with different wall thicknesses are obtained by different test and analysis methods.The results show that as the content of Mn is 0.4%~0.65%,the content of Mg is 0.17%~0.5%,and the Mn/Mg ratio reaches 1.69~1.90,the tensile strength,yield strength,and elongation of HL-111 alloy with a wall thickness of 2~3mm can reach more than 280MPa,120MPa and 10%respectively,and the mechanical properties of the material are greatly improved.In addition,the tensile strength,yield strength,and elongation of HL-111 alloy after T5 heat treatment at 165℃for 510min reach 302.36 MPa,190.32 MPa,and 8.42%.The precipitated phase of Mg2Si leads to changes in strength and elongation.

等离子熔覆CrMnFeCoNiMo_(x)高熵合金涂层的组织、硬度和腐蚀性能

采用等离子熔覆技术在20钢表面制备了不同成分的CrMnFeCoNiMo_(x)(x=0、1、1.5)系高熵合金涂层。通过光学显微镜(OM)、扫描电镜(SEM)、能谱仪(EDS)及X射线衍射仪(XRD)等分析了涂层的微观结构;利用显微硬度计和电化学工作站分析了涂层的硬度和耐蚀性。结果表明:在不含Mo的高熵合金(HEA)涂层中存在大量的枝晶和胞状晶,添加Mo元素后主要为等轴晶。3种涂层的基体组织主要为体心立方(BCC)结构,Mo元素的添加使涂层中形成了一定量的第二相。CrMnFeCoNiMo_(1.5)涂层的第二相含量最多,硬度最大(约720 HV0.3),约为基材的4倍。Mo元素添加后,涂层的耐蚀性显著提升,CrMnFeCoNiMo_(1)涂层的耐蚀性能最好,腐蚀速率为0.141 mm/year,约为基材的1/20。

右江盆地大际山U-(Mo)矿床围岩蚀变特征及微量元素迁移规律——对区域内U、Au成生关系的指示

位于扬子地块西南缘的右江盆地,是全球第二大的卡林型Au矿(共伴生有Sb、Hg、Tl异常/矿化)矿集区,有着滇黔桂“金三角”的美誉。值得注意的是,该区除发育Au(-Sb-Hg-Tl)矿床外,还产有大量赋矿岩性和控矿构造相似的U矿床(点),成矿特色鲜明。前人对该区Au矿开展了大量研究,而U矿研究较少,对U、Au的成生关系尚不清楚。基于此,文章选取右江盆地内典型的U矿床——大际山U-(Mo)矿床为研究对象,通过开展岩矿相学研究和地球化学分析,厘定了矿化的围岩蚀变为硫化、沥青质化、磷铝锶石化、硅化和伊利石化,揭示了矿化过程中Re、Tl、Mo、U、Cd、Ni、Co、As、Sb、MREE的相对富集。蚀变矿物组合及元素迁移规律约束大际山U-(Mo)矿床中成矿物质可能来源于牛蹄塘组,成矿流体应为还原性有机流体与地表-近地表酸性、氧化性流体的混合,矿质沉淀发生在低温、酸性、还原环境中。综合分析认为,右江盆地内U、Au分布特征及矿床成因具有明显差异,二者应是不同成矿事件的产物。

动载荷下Mn13Cr2Mo高锰耐磨铸钢形变硬化行为

采用分离式Hopkinson压杆(SHPB)的测试方法对不同冲击载荷下典型高锰铸钢Mn13Cr2Mo的形变硬化行为进行了系统研究。结果表明,随着气缸压强由0.2MPa增加至0.8MPa,Mn13Cr2Mo铸钢形变硬化过程可近似分解为线性硬化、非线性硬化两阶段;当压强为0.2 MPa时,线性硬化维持至约107 MPa时开始向非线性硬化阶段转变。当压强由0.4 MPa增加至0.6 MPa时,线性硬化向非线性硬化阶段转变的临界强度由123 MPa增加至356 MPa;在非线性硬化阶段,当压强高于0.4 MPa时高锰钢的应变硬化率明显提高。综合考虑线性硬化向非线性硬化的转变强度以及高锰钢的加工硬化速率,当气缸压强高于0.6 MPa时,由线性硬化向非线性硬化阶段转变的临界强度达到约356 MPa。材料在非线性硬化阶段的应变硬化率较高,此时试验用Mn13Cr2Mo高锰耐磨铸钢形变硬化能力被充分激发。

Influence of rare earth Ce on hot deformation behavior of as-cast Mn18Cr18N high nitrogen austenitic stainless steel

The hot deformation behavior of Mn18Cr18N and Mn18Cr18N+Ce high nitrogen austenitic stainless steels at 1173-1473 K and 0.01-1 s^(-1) were investigated by thermal compression tests.The influence mechanism of Ce on the hot deformation behavior was analyzed by Ce-containing inclusions and segregation of Ce.The results show that after the addition of Ce,large,angular,hard,and brittle inclusions(TiN-Al_(2)O_(3),TiN,and Al_(2)O_(3)) can be modified to fine and dispersed Ce-containing inclusions(Ce-Al-O-S and TiN-Ce-Al-O-S).During the solidification,Ce-containing inclusions can be used as heterogeneous nucleation particles to refine as-cast grains.During the hot deformation,Ce-containing inclusions can pin dislocation movement and grain boundary migration,induce dynamic recrystallization(DRX)nucleation,and avoid the formation and propagation of micro cracks and gaps.In addition,during the solidification,Ce atoms enrich at the front of solid-li-quid interface,resulting in composition supercooling and refining the secondary dendrites.Similarly,during the hot deformation,Ce atoms tend to segregate at the boundaries of DRX grains,inhibiting the growth of grains.Under the synergistic effect of Ce-containing inclusions and Ce segregation,although the hot deformation resistance and hot deformation activation energy are improved,DRX is more likely to occur and the size of DRX grains is significantly refined,and the problem of hot deformation cracking can be alleviated.Finally,the microhardness of the samples was measured.The results show that compared with as-cast samples,the microhardness of hot-deformed samples increases signific-antly,and with the increase of DRX degree,the microhardness decreases continuously.In addition,Ce can affect the microhardness of Mn18Cr18N steel by affecting as-cast and hot deformation microstructures.

Cr-Mn-Mo低合金钢中白亮带对力学性能的影响

对比分析了Cr-Mn-Mo低合金钢连铸坯中白亮带处与附近基体的化学成分,检验了淬火态及调质态Cr-Mn-Mo低合金钢管的显微组织和力学性能,研究了白亮带对材料力学性能的影响。结果表明:白亮带在连铸坯中的化学成分呈负偏析;淬火态时,白亮带处的硬度与基体相差较大,显微组织也有差异;调质处理后,白亮带与基体的显微组织已无明显差异,硬度差距大幅减小,强度和冲击韧性也无明显差异。因此认为,白亮带对Cr-Mn-Mo低合金钢调质态的整体性能影响不大。

Effect of Rare Earth Elements on Austenite Growth Dynamics of Steel 9Cr2Mo

The growth dynamics of austenite grain was investigated in steel 9Cr2 Mo with different rare earth(RE)element addition.The results show that austenite grains of steel 9Cr2 Mo can be refined and their growth can be restrained by adding a certain amount of RE.According to the results,the n and Q were calculated and the mechanism of the refinement of austenite grains was discussed.