苏联的工业硅化学成分标准

标准代号等级51不小于 % 杂质不大于%{c·{F百A‘公a{黑Mn Ti S P C 0总和KP00r〔减二TKPOKPI2169一69KPZKP399.0今8 .898.097.096.00 .40.50.71 .00 .40.40 .60 .81 .5].01 .22 .03 .04 .0‘纽.勺月‘n甘 .…0‘U﹄n.,止Fe ta8 1999850 .40.6Q .91 .52 .00.6070 .58 198.58 19897.5971 .50 .40 .60 .91 .52 .00.6“Hee30382 .00 .68 19781963 .02 .5C .84 .03 .50 .8丹亡﹃匕99…月、.‘....月.....‘一......胜.吸.t..............苏联的工业硅化学成分标准~~…     

美国常用钛合金的化学成分

ASTM合金牌号 Al V Mo Sn Pd Zr Fe O H N CGrade1 - - - - - - 0 .2 0 0 .1 80 .0 1 5 0 .0 3 0 .1 0Grade2 - - - - - - 0 .30 0 .2 5 0 .0 1 5 0 .0 3 0 .1 0Grade3 - - - - - - 0 .30 0 .35 0 .0 1 5 0 .0 5 0 .1 0Grade4 - - - - - - 0 .50 0 .40 0 .0 1 5 0 .0 5 0 .1 0Grade5 5.5～ 6.753.5～ 4 .5- - - - 0 .40 0 .2 0 0 .0 1 5 0 .0 5 0 .1 0Grade 6 4.0～ 6.0 - - 2 .0～ 3.0 - - 0 .50 0 .2 0 0 .0 2 0 0 .0 5 0 .1 0Grade 7 - - - - 0 .1 2～ 0 .2 5 - 0 .30 0 .2 5 0 .0 1 5 0 .0 3 0 .1 0Grade 92 .5～ 3.52 .0～ 3…     

真空镀膜用的铝钛合金的研制

一前言由于铝箔具有许多特点:1.银白色的金属光泽;2.无毒、无味、无臭;3.热光反射性能较高;4.易于压花、印花和染色;5.有良好的防潮性及保味、防虫、防臭;6.传热性好,低温不脆化。因此,铝箔是食品、香烟、药品、器皿、照相底板的包装材料,也     

从技术与经济的角度看蠕虫状石墨铸铁的应用

一般定义蠕虫状石墨是石墨的一种形式,它不同于片状石墨和球状石墨,在某种意义上介于这两者之间。根据钢铁检验书称其为“P-石墨”,而VDG-标准第442页和C.K.Donoho称它为“Ⅲ型石墨”。蠕虫状石墨这个名称是根据C.K.Donoho和R.D.Schelleng的介绍而延用的。很遗憾,曾经产生过一些误解,后来G.N.J.Gilbert和M.G.Day也用同样的名称称呼非常精细的片状石墨。     

基于C#.NET的开放式数控系统的研究与开发

在分析开放式数控系统体系结构的基础上,讨论了采用C#.NET作为开放式数控系统开发工具的优势.深入研究了基于C#.NET数控系统的关键技术--设备驱动技术,并根据设备供应商提供的驱动模块不同,提出了三种相应的解决办法.其一是直接使用设备商提供的基于.NET的控件;其二是利用设备提供的动态链接库(DLL),在C#.NET中直接调用;其三是利用设备提供的LIB函数库,创建自己的DLL供C#.NET调用.最后在C#.NET环境下开发了一个NC嵌入PC型数控系统,该系统完全满足开放式数控系统的要求.     

一些国家铝合金半成品的分布

一一一-一一一一一~一一-一耳一- }1970年1979年一品%一国家和产品分类重量,000吨{占总半成品}百分比,%{{l}重量,000吨占总半成百分比,美国(净装运量总计)薄板和厚板挤压型材铝箔裸露的钢芯铝线和电缆绝缘的线和电缆裸露线轧制棒,条和型材锻件拉拔管焊管变形制品合计铸件粉末和铝膏4020.96002 .21673.1746 .64 1 .68 162865.91064.7口曰O份,曰O口OJ八U八几︺OU通住,.︷,土2532261 18.042 .46 .35 .62 .91 .11 .21 .41 .01 .095 .049.982 .566 .942 .043 .537.9 :座︸一衬︸︸勺nj5042.0903 .3叮‘n :﹃U tlR 113244.8683 .392.82 .356.9…     

铁的稳定同位素表

原子序数Z原子质量数中子数N相对分布量 %同位素质量原子量2 65 45 65 75 82 83031325 .8191.6 42 .2 10 .345 3.9396 2 15 5 .9349325 6 .935 3945 7.9332 725 5 .84 7注 :1.原子质量数massnumber2 .相对分布量relativeabundance(或丰度 )3.表中后两项以C12 =12 .0 0 0 0 0 0为单位铁的稳定同位素表     

适用的就是最好的浅谈企业的人才招聘

企业的发展,离不开人才的推动,如今,企业的人力资源部门撒开网到处寻觅合适的人才.为了更有利于企业发展目标的实现,有些企业不惜重金招聘高层次的人才.但在实际情况中,所谓的"高层"并不见得都那么适用.有些人才要么与企业的要求不适应,要么就是对企业所提供的条件不满足,挂冠而去.由此来看,也并不见得高层人才越多,企业就越有希望.在很多情况下,结果可能反而是这样,就企业而言,需要的人才也许不一定是最优秀的,但往往是最合适的.     

九十年代流体动力的目标

前言本文简要介绍美国三位著名流体动力专家 E.C.Fitch,R.K.Tessman 和 I.T.Hong 根据其长期经验和调查分析,对九十年代流体动力的目标所作的预测。他们信守的原则是:只有根据现实的发展趋势,建立切实可行的目标,才是对未来的最好准备。并依此规定未来的发展对策,值得借鉴。     

耐候性粉末涂料的新进展

机电部重庆五九研究所研制的新的耐候性粉末涂料已经完成,正进入推广应用阶段。这种新的耐候性粉末涂料,是聚酯/T.G.I.C型粉末涂料的新发展。聚酯/T.G.I.C型粉末涂料在七十年代已进入欧洲市场,至今仍得到广泛应用,在粉末涂料中它的产量约占18％。这种粉末涂     

PCD刀具加工有色金属的研究

本文主要研究PCD刀具加工有色金属时刃口及后刀面的刃磨质量对切削表面质量的影响。首先对PCD刀具切削有色金属模型进行了分析研究,然后分别采用金属结合剂金刚石砂轮、树脂结合剂金刚石砂轮和陶瓷结合剂金刚石砂轮刃磨出三把不同质量的PCD刀具进行了切削对比试验,并用扫描电镜对切削表面微观形貌进行了观察分析,发现加工有色金属时,PCD刀具后刀面与刃口刃磨质量对切削表面质量有着同等重要的影响作用。     

A study on instantaneous cutting force coefficients in face milling

In this paper, the characteristics of instantaneous cutting force coefficients in face milling are studied. In order to estimate instantaneous cutting force coefficients in face milling, the relationships between instantaneous cutting force coefficients and measured cutting force signals are derived. A series of experiments are then conducted to study the natures of instantaneous cutting force coefficients. The relationships between instantaneous cutting force coefficients and other cutting parameters are also established. It is found that the normal force coefficient is mainly affected by chip thickness and cutting speed; the vertical force coefficient is mainly affected by chip thickness, cutting edge length and cutting speed; and that the horizontal force coefficient is not only affected by chip thickness, cutting speed and length of cut, but also the variation rate of chip thickness.     

硬质合金可转位刀片刀尖圆弧半径对切削过程的影响

通过试验 ,分析了硬质合金可转位刀片刀尖圆弧半径对金属切削的切削力、断屑范围和切屑形态的影响。结果表明 ,加大刀尖圆弧半径会显著加大 y向分力 ,使 z向分力略有下降 ,而断屑范围缩小 ,并增加切屑缠绕的可能性     

高温合金切削刀具的研究现状及进展

高温合金具有较高的强度、抗高温氧化性等性能,被广泛应用于各种领域中,其加工时切削温度高、加工硬化严重、刀具磨损严重,是最难加工的材料之一。本文综述了国内外高温合金切削刀具的研究现状。阐述了高温合金的切削特性,重点对高速钢、硬质合金、涂层硬质合金、陶瓷、PCVB这几类高温合金切削刀具材料的研究现状进行了分析;同时,也对国内外切削高温合金刀具的结构、切削加工工艺参数以及磨损机理的研究现状进行了概述。在此基础上,发现高温合金切削刀具虽然已经研发设计出了多种新刀具材料、新切削工艺参数,但仍然需要进一步了解影响刀具性能的因素及刀具磨损机理。因此,本文提出了建立评估刀具使用性能体系和研发高性能的刀具材料是高温合金切削刀具的主要研究方向。     

氧-天然气切割和焊接技术研究

研究了氧-天然气金属切割和焊接技术.结果表明:通过设计出优质快速切割喷嘴和双层焊接焊炬,采用合适的切割和焊接工艺规范和措施,氧-天然气切割和焊接技术能获得良好的切割质量和焊接质量,且能满足一般效率要求;与氧-乙炔气体相比,氧-天然气切割和焊接技术成本最低,具有显著的推广应用价值.     

曲轴车-车拉加工工艺切削模拟试验研究

车-车拉工艺是现今汽车发动机曲轴主轴颈粗、半精加工中广泛应用的切削工艺。本文对车-车拉加工工艺流程进行了阐述,选取该工艺中最为复杂的斜刃车拉加工工序为研究对象,对涂层硬质合金斜刃车拉刀片的几何结构及涂层特点进行了分析。并基于Schroeter R B等人的试验方法,通过对刀具安装方式和工件材料的设计,在CNC斜床身车床上建立了切削模拟试验平台。通过改变总切深ap与进给量f,对斜刃车拉加工工艺进行了切削模拟试验,研究了斜刃车拉刀片的受力变化特点,以及上述两参数对切削力、加工表面圆度与加工表面粗糙度的影响特征。研究结果表明:在切削速度170 m/min条件下,斜刃车拉切削参数在总切深ap=0.15～0.2 mm,f=0.1～0.15 mm/r范围内选取,能获得较好的切削效果。     

A calculating method for the fewest cutting passes on sapphire substrate at a certain depth using specific down force energy with an AFM probe

This paper proposes the innovative concept of specific down force energy (SDFE) and applies it to nanoscale multi-pass cutting using an atomic force microscopy (AFM) probe as a cutting tool. This paper defines SDFE as the down force energy dividing the volume of material removed of the workpiece by the AFM probe. Experimental data and the calculation results indicate that the SDFE values of different down forces and in different cutting passes are close to a constant value. Adopting the SDFE theory, this paper calculates objective functions through step-by-step adjustments of the increased cutting depth under some constraint conditions. These conditions require that the shape of probe is already known and is within the range of machinable down force of probe, and that the requirement of convergence error functions of SDFE and objective cutting depth are met. This paper uses the proposed method to identify the fewest cutting passes that can achieve the objective cutting depth under suitable down force action. Finally, this paper reports experiments using an AFM probe cutting tool to carry out nanoscale cutting experiments on the surface of sapphire substrate for cutting nanoscale V-shaped grooves in different cutting passes under different down force actions. This study compares the cutting depth values of different nanoscale grooves in the central area with the theoretically calculated results. A comparison of these results shows that the down force and cutting passes required to achieve the objective cutting depth using the proposed method are very close to experimental results using the same down force and cutting passes. These results verify the feasibility of the proposed method in finding the fewest cutting passes for cutting a specific depth using an AFM probe.     

Effect of machining conditions on specific tangential forces

This paper deals with different hypotheses regarding the resistance of deformable material that is subject to plastic strain. For analysing cutting processes, a new cutting layout with a single shear plane is proposed here to calculate the specific tangential forces. The specific tangential forces in the different shear zones were examined by experiment to verify one of the hypotheses in question. These analyses verified that the forces depend fundamentally on cutting parameters and cutting layouts. Hence, it is necessary to take account of a correlation between yield point and deformation temperature, when determining the mechanical properties of the cutting material during machining. It is suggested here to determine the mechanical properties from the conditions compensating the hardening and the softening of the cutting material.     

微槽刀具切削GH4169的工件表面完整性研究

针对如何改善零件的已加工表面完整性,提高零件的服役能力,文章基于温度场形状开展切削GH4169的刀具前刀面微槽设计研究,设计并制备了新型微槽刀具,并将原刀具和微槽刀具加工后的工件表面完整性进行对比试验研究,结果表明:微槽结构改变了刀具的平衡力系,使其切削力和切削温度降低,进而使得在推荐切削参数下,使用微槽刀具切削的表面质量优于原刀具,粗糙度降低了22.96%,残余拉应力降低了30.7%,工件表面显微硬度随切削速度的增加而加剧,且微槽刀具切削后的工件硬化程度和深度均有所降低。     

基于FAHP-GRA的绿色制造机床切削液选择

在制造行业机械加工过程中,切削液的选择使用是带来环境污染程度的重要因素,为了解决切削液在选择使用时带来的环境污染问题,考虑到绿色制造的理念,运用模糊层次分析法(fuzzy an-alytic hierarchy process,FAHP)和灰色关联分析法(GRA)相结合建立数学模型并求出最优解,针对切削液的性能,成本价...