埋置沸腾床中管件耗损与HCl物实验室模拟

采和实验室流态床燃烧器模拟装置评定氯化物对埋管耗损的影响。该模拟装置能重现埋管底部密集颗粒的冲刷，其运行参数可控，以接近沸腾流态床所遇工况，ＨＣl被选为Ｃｌ源加 入流态化空气中，其含量在５０～４００ｕｇ／ｇ间可调，试验温度范围由室温至４００℃，以１０１８低碳钢棒代表埋管，床体为平均粒度８００ｕｍ的工业用ＳｉＯ２砂，结果表明，ＨＣｌ明显地加剧材料的耗损，且其随ＨＣｌ浓度的增加而加剧，本研究所获ＨＣｌ加     

流态床冷却技术的应用与发展

流态床的问世已有60年了。但直至本世纪60年代，流态床才被引入金后热处理领域。几十年来，热处理工作者在热处理流态庆特性研究、结构设计和工艺应用等方面已经取得了可喜的成就。现在，流态床热处理已成为金属热处理的重要方面[1，2]。在热处理各个技术环节中，冷却过程是热处理过程中最后一个需要有效控制的环节。用流态床进行热处理冷却，不仅可克服使用水、抽、聚合物、盐裕等作冷却介质的缺点，并可实现冷却可调［3］。1用于冷却的流态床的分类与特性［4~7］用于热处理冷却的流态床，根据其流化系统的组成分为三大类。1.1气一固冷却床…     

流态床的传热学研究

对流太床的传热过程进行了分析，提出了计算流态床热传递过程的数学模型，运用本模型可测定不同工作状况上的流态床换热系数，为正确制定热处理工艺奠定基础。     

流态床热处理炉的经济效益分析

采用流态床对金属进行热处理，具有经济、无污染和零件处理质量高的优点，这已为国内外生产实践所证明。我厂生产冶金工业用轧辊和剪刀，批量少，但对质量要求较高，采用常规热处理设备无法满足生产要求。我厂于1989年购进了75kW、125kW两台大型流态床热处理炉，使用四年多来，已累计热处理各种工件2000t，产值600万元，利润90万元，产品合格完98％，收到了明显的经济效益。现根据我厂生产实践，谈谈采用流态床热处理的特点及优点。流态床与盐浴护相比，有启动容易、能耗小、操作简便、无环境污染等优点，比盐浴炉先进。1单位能耗据1990年…     

译海掇英

钢丝流态床韧化处理人们与使用重金属(如铅浴)或有害物质(如熔盐浴)作斗争中,钢丝流态床韧化处理工艺在钢丝领域已占有重要的位置。本文论述了流态床韧化处理工艺的物理、化学及热力学优点: 流态床内淬火可以按照流态床的温度分布曲线加热使钢丝韧化处理得更快。流态床韧化处理提供了一个条件,可以按照钢丝的热分布曲线分区建立不同温度的淬火气氛。除了有可能优化淬火外,又因不存在铅浴拖拉钢丝,增加了化学浴效率,也减少了拔丝过程中的断丝。流态床无需木炭覆盖或作防污染处理。鉴于上述优势,流态床韧化处理取代铅     

ECR微波等离子体源离子渗氮

研究了一种新的低温渗氮方法－－电子回旋共振微波等离子体源离子渗氮。对纯铁、４５负和３５ＣｒＭｏ钢试样在１５０￣３５０℃进行渗氮处理，测定了渗氮层的硬度和晶体结构，结果表明，纯铁在低于２００℃的温度即可获得连续分布的表面氮化物层，３５ＣｒＭｏ钢在低于２５０℃温度处理也可获得离好渗氮层。     

流态床炉的低流量渗氮处理工艺

自从流态床炉本身作为常规热处理设备的一项富有生命力的替代装置以来,研究的重点已经从基础原理转移至工艺的最优化上。作为恰当的例证,本文将研究一种能够降低流态化气体耗用量多至90％的工艺。所以,该工艺特别适用于较深层0.004英寸(0.1)毫米)的渗氮处理.本文重点将涉及原理、经济、冶金以及该技术的有关应用。     

流态床热处理炉的发展现状

本文综述了流态床热处理炉的开发及应用现状，介绍了国内外各种最新流态床热处理炉的结构及特点。     

钢和铸铁在流态床中的加速冷却

1. 序言由于流态床中的热传导比空气中快,因此它可用以作为热处理工件的淬火,如果是细颗粒的流动粒子且具有高的热容量,那冷却就更快。若把作为流态床流动所必需的最小流动气体的流速提高到同最高导热系数相适度的速度,则将大大提高导热系数。当进一步提高流速时,由于流态床中粒子间接触面积的减少,热传导又降低。这样,就给出流速一个合适的工作范围,这个流速     

流态床淬火冷却

流态床作为淬火介质,在常温下冷却速度介于油和空气之间而加热后,则可作为分级淬火和等温淬火的介质。在本文中,作者测定了影响特性曲线的各种参数,并叙述了一些应用的实例。前言不少文献介绍了在周期式罐状炉内以气流流化氧化铝微粒的流态床技术〔1、2〕这些文章一般都着重于流态床在单件或小批零件的加热应用,而本文的重点则是流态床在淬火冷却中的应用。热处理车间为获得淬火的最佳条件,提供一种适当的淬火介质是决定操作成败的关键。虽然现在常用的淬火     

An Investigation on Low-Temperature Thermochemical Treatments of Austenitic Stainless Steel in Fluidized Bed Furnace

In this study, the feasibility of using an industrial fluidized bed furnace to perform low-temperature thermochemical treatments of austenitic stainless steels has been studied, with the aim to produce expanded austenite layers with combined wear and corrosion resistance, similar to those achievable by plasma and gaseous processes. Several low-temperature thermochemical treatments were studied, including nitriding, carburizing, combined nitriding-carburizing (hybrid treatment), and sequential carburizing and nitriding. The results demonstrate that it is feasible to produce expanded austenite layers on the investigated austenitic stainless steel by the fluidized bed heat treatment technique, thus widening the application window for the novel low-temperature processes. The results also demonstrate that the fluidized bed furnace is the most effective for performing the hybrid treatment, which involves the simultaneous incorporation of nitrogen and carbon together into the surface region of the component in nitrogen- and carbon-containing atmospheres. Such hybrid treatment produces a thicker and harder layer than the other three processes investigated.     

Attaining the Steady State of the Nitriding Potential after a Change of NH3 Atmosphere Flow Rate during the Gas Nitriding Process

In single and multi-stage nitriding processes, each stage is characterized by the following parameters:temperature and time, type and composition of incoming atmosphere, as well as the set value of the nitriding potential. In the case of an atmosphere composed of raw ammonia and dissociated ammonia (NH3-NH3diss), the set value of the nitriding potential can be achieved by a change of the incoming atmosphere make-up, while in the case of atmospheres comprising NH3 and NH3 - N2 - by a change of the atmosphere flow rate. The time needed to reach a stabilized state, after the initiation of a change in the atmosphere gas mix can be assessed relatively easily. The problem is much more complex if we want to predict the time of reaching a new stabilized state following a change in atmosphere flow rate. The time of reaching stabilized state is, in this case, a complex function of the flow rate of the atmosphere which forces the potential change, and of temperature. This problem, in the case of the NH3 type atmosphere, is the subject of investigation in this work. Factors are discussed, affecting the rate at which stabilized state is reached by the system after the introduction of a disturbance, necessary to attain the required nitriding potential.     

柴油机曲轴的离子渗氮工艺改进

采用脉冲式离子渗氮炉对柴油机曲轴进行了辉光离子渗氮处理。试验表明，在渗氮炉中放入含La、Ce的混合稀土，或在离子渗氮过程中通入少量CO2气体，都能明显促进离子渗氮，提高曲轴的耐磨性。     

阴极电压和供氮方式对纯氮离子渗氮的影响

分别研究了在500、600、650和700 V阴极电压条件下采用连续供气抽真空和间歇供氮闭炉的方式进行纯氮离子渗氮的工艺及机理.通过对间歇供氮闭炉离子渗氮层显微组织、相组成和硬度梯度的测定与分析,计算和验证了该工艺中N2分子临界离解能.结果表明,纯氮离子渗氮的活性氮原子来自于经阴极位降区加速的高能N 2与中性N2分子间的非弹性碰撞,离解N2分子的N 2离子临界能为48.64 eV,相应的阴极电压门槛值为650 V.纯氮离子渗氮工艺除要求阴极电压高于650 V外,间歇供气闭炉渗氮也是必备条件,在一定温度和足够高的阴极电压下,只有采用间歇供氮闭炉方式进行离子渗氮,从N2分子才能离解出足够多的活性氮原子,使试样表面产生明显的渗氮效果.     

Solid Solution Nitriding Technology of 15Cr-7.5Mn-2.6Mo Duplex Stainless Steel

NEW DEVELOPMENT of stainless steel mainlyoccurs in area of nitrogen-containing austenitic steeland austenitic-ferritic duplex steel.It has been proposedthat a nitrogen-alloyed steel can be considered as anhigh nitrogen steel(HNSs),when the nitrogenconcentration is higher than0.4wt%in austenitic steelsand higher than0.08wt%in martensitic steels'M1.Butthis concept has been developed for the newmanufacturing technologies of HNS,such as pressureor powder metallurgy.In addition,the chemical…     

氮势控制技术及其应用

简要介绍了渗氮机理及氮势控制技术，并在GN70／120型井式渗氮炉内进行了可控渗氮试验。结果表明，采用HydroNit氢探头能精确测量和控制炉内氮势，有效降低渗层氮浓度，减少表面白视层厚度，满足高质量渗氮要求。     

Effect of Electric Potentials on Microstructure,Corrosion and Wear Characteristic of the Nitrided Layer Prepared on 2Cr13 Stainless Steel by Plasma Nitriding

Plasma nitriding is a widely used technology to enhance the surface performance and extend the service life of alloy parts.The current research mainly focuses on the influences of time, temperature, gas type and pressure parameters on nitriding behavior, while fewer studies have been conducted on the electric potential. This paper mainly reports the effect of the electric potential on nitriding behavior. Test conditions were set using cathodic, anodic and floating potentials in a plasma nitriding furnace. 2Cr13 stainless steel was nitrided at 450 °C for 5h in an NH_3 atmosphere. The experimental results show that the nitriding treatment can be well performed under the different electric potentials, but differences exist in microstructures, morphologies and performance results of the modified layers. The thickness and hardness values of the nitrided layer are ranked as follows: cathodic [ anodic [ floating potential. The anodic nitrided surface has an obvious particle deposition layer composed of nitrides and oxides. Electrochemical and tribological experiments show that the corrosion resistance and wear resistance were significantly improved after a nitriding treatment using the three electric potentials. Moreover, the floating nitriding treatment resulted in the best tribological performance and corrosion resistance.     

新型真空脉冲渗氮设备

本文介绍了一种全新的真空脉冲渗氮设备，由加热炉罩、内罩、底座、真空系统、配气系统和控制系统等部分组成，其主要特点在于：采用弹压式触头配电；操作方便；一个加热炉罩可配备多个炉座，能进行脉冲渗氮处理或其它低温化学热处理、真空回火快冷处理、充气保护回火处理等多种工艺加工；热效率高，节能效果显著；控制系统采用了先进的计算机程序控制技术、人机对话技术以及先进的执行元器件如大功率固态继电器等。     

Tempering of carburized steel in a fluidized bed

Conclusions The decomposition of retained austenite in carburized steel 18Kh2N4VA during tempering at 650°C in a fluidized bed is the same as that with tempering in a lead bath and occurs twice as fast as with tempering in the electric furnace. This can be explained by the greater precipitation of carbides on lattice defects due to rapid heating in the fluidized bed, and the slowed redisribution of nickel in the solid solution.Ural Polytechnical Institute. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 1, pp. 58–61, January, 1973.     

钢表面获得单相ε化合物层的二段氮碳共渗工艺

在井式气体渗氮炉中,采用氨气加二氧化碳和氨气加甲醇两段法对碳钢和合金钢进行了氮碳共渗,通过控制共渗温度和氮势等主要工艺参数,使氮碳共渗表层化合物层获得单相ε组织,并探讨了温度对不同材料共渗层组织、渗层深度及显微硬度的影响.结果表明:在570 ℃和615 ℃下氮碳共渗都可在表层获得单相ε组织,并随温度的升高,渗层深度和显微硬度都明显提高,能满足不同材料多种零件的使用要求.