利用差示扫描量热法评价润滑油的高温抗氧化性能

本文介绍了利用差示扫描量热法检测高温润滑油氧化诱导时间、起始氧化温度、沉积物形成趋势等指标的方法。．利用差示扫描量热法对酯类润滑油及其抗氧剂的高温抗氧化性能进行了评价。     

用差热天平对锅炉垢成分进行研究

本着节约能源,笔者采用差热天平对锅炉垢进行了实验性研究,探讨了锅炉垢的主要成分,提出了锅炉使用中应注意的问题.     

润滑油基础油高温氧化沉积特性的研究

通过对比研究，利用加压差示扫描量热双峰法考察了加氢异构脱蜡基础油和溶剂精制基础及其不同组分的高温氧化及沉积物生成特性，并对添加剂的影响进行了研究。结果表明：异构脱蜡基础油和饱和烃的氧化安定性分别低于溶剂精制基础油和芳烃组分，但抗沉积物生成特性好于后者.添加剂对两种基础油氧化安定性有不同的影响，但会导致沉积物增多。     

45钢大试样缩短淬火加热保温时间的研究（二）

3.性能变化规律,总的符合随着强度、硬度升高,塑性、韧性降低的趋势。在某一保温时间,出现σb的峰值及与之对应的αk最小值或αk降低较多,如图1所示。A、B试样保温时间是20分,C、D试样保温时间是60分。 4.一般性能波动较小,各最大和最小性能相比,零保温和最长保温时间试样相比,性能变化都不大,如表5所示。强度变化稍大;直径增大,性能波动增加,淬透性有所降低,大试样整个截面,难以同时或短时达到奥氏体转变及均匀化的理想程度,如D和D5-1可能如此。 5.最佳综合机械性能及其对应的保温时间如表6所示,其中零保温节能效果最佳。     

差示扫描量热法测定ABS树脂的氧化诱导时间

采用差示扫描量热法测定了ABS树脂的氧化诱导时间。讨论了在氧化诱导时间测试过程中的各种影响因素,确定了适当的测试条件。提出了使用氧化诱导时间测试方法需注意的问题。方法简单快速,重复性好,相对标准偏差小于5％。     

新型燃烧器在锻造炉上的应用

我厂锻造炉原烧油改为烧天燃气，采用平焰烧咀，该烧咀具有加热速度快，工件加热温度均匀燃烧稳定，氧化烧损少，炉龄寿命长，充分利用烟气余热能使空气预热300℃，节省天然气热效率高。     

GH34钢在高温恒定载荷下的开裂界限

用预制裂纹试样测定了燃气轮机叶轮材料GH34钢在550℃恒定载荷下的开裂界限K_(1t),并由此估算了在一定期限内(1000h),在工作应力下不扩展的安全裂纹尺寸。所得结果对于保证燃气轮机的安全运行,起了一定作用,并经受了实际考验。     

高温应变片在高温下的性能特性

近十几年来,高温称重传感器在冶金工业部门的应用越来越普遍。但是,由于高温称重传感器所用的高温应变片和高温胶粘剂等的特殊性,在制作过程中必须经繁杂的处理和测试工序,使产品生产效率降低、成本提高。人们试图改变这种状态,但是由于有关高温应变片在高温下性能的系统资料甚少,给工作带来不少困难。为了增加人们对传感器用高温应变片的了...     

高温环境下超声电机的机械性能测试

研制了一种在高温环境下测试超声电机机械性能的装置,该装置包含了温度环境试验箱、转速转矩测量仪以及连接轴,提出了在高温环境下测试超声电机机械性能的方法.通过该装置和试验方法,对超声电机进行了高温环境试验,其环境温度为50～150℃.试验结果表明:随着环境温度升高,超声电机的转速下降;当环境温度<70℃时,超声电机最大力矩随着温度的上升而增加;当环境温度>80℃时,最大转矩随着温度的上升而下降;当环境温度到150℃时,超声电机不工作,超声电机在高温环境下需要降低其性能使用.该试验装置和试验方法同样适用于低温环境.     

Wear of low temperature nitrided steels under different wear processes

A programme of tests has been carried out to assess the wear resistance of three low temperature nitriding treatments when compared with the untreatedv steel and a standard cyanide case-hardening treatment, under conditions of scuffing, abrasion, fretting and corrosion. The main conclusion is that low temperature nitriding is most suited to applications where scuffing and corrosion are the main wear mechanisms and that the resistance to abrasion and fretting is poorer in general than that of traditional case-hardening. Therefore, care should be taken in assessing the wear process in any application in which these treatments are used. Reference is also made to the wear mechanisms in the different tests.     

高温工况下热工参数测量的系统解决方案的研究

热参数测量的巨大需求是为了准确测量温度监测参数,以提高电力设备的安全性和效率,确保设备的安全运行。然而,在电力生产本身,由于各种原因,热参数测量不正确可能会不时发生,这会导致热保护系统发生故障或停止。该文总结分析了设备运行过程中常见的测温问题,提出了维护和操作解决方案。     

Research on oxidation wear mechanism of the cast steels

The uni-directional pin-on-disk wear tests were performed in elevated-temperature air at 400 °C for the Cr–Mo–V cast steels with different compositions. Morphology, composition and structure of worn surfaces, oxidation films and matrix were examined using SEM, EDS, XRD and TEM. The relations between oxidation wear rate and matrix were studied. The mechanism of wear was clarified. Under elevated-temperature air at 400 °C, typical oxidation wear was presented in the cast steels. Oxidation of worn surface and fatigue delamination of oxide film proceed alternatively during sliding. As there are not coarse second phases in steel, oxide film is main factor in determining wear rate, which conforms to Quinn's oxidation wear theory. In this case, delamination of oxide film was found to take place inside oxide film or at interface of matrix and oxide film. This is classified as mild oxidation wear with lower wear rate. As coarse second phases exist in steel, the wear rate is strongly dependant on microstructures of matrix. In this case, oxide film delaminates from the inside of matrix under oxide film. This is classified as severe wear with high wear rate.     

Elevated temperature erosion of steels

The elevated temperature erosion behavior of several commercial ferritic and austenitic steels was determined over a range of temperatures from room temperature to 900 °C. It was determined that all the steels had constant or decreasing erosion rates as the test temperature was increased until a temperature was reached where a marked increase in erosion rate began to occur with temperature. Austenitic steels were determined to have lower erosion rates than ferritic steels and their hardness had no correlation with their erosion rate. All the steels tested eroded by the platelet mechanism of erosion.     

Electrochemical mechanisms of the dissolution of metals and the concomitant oxidation of lubricating oils under high temperature friction conditions

In used motor oils worn and dissolved metals (e.g. copper, iron, Ni-Cr and aluminium) are found as a result of erosion and/or corrosion of the movable engine parts. These suspended and dissolved metals cause an oxidative deterioration of the motor oil, as indicated by its increase in viscosity and acidity, and a decrease in its detergency etc. The recent work of Abou El Naga and Salem, carried out under controlled laboratory conditions, provides excellent data for examining various mechanistic proposals.It is shown here that the oxidation of the oil occurs through a peroxide route involving electrochemical (on open circuit) reduction of oxygen with metal dissolution (i.e. corrosion) as its conjugate anodic reaction. In fact, it is found that the amount of oil oxidized is proportional to the amount of metal corroded, irrespective of the nature of the metal. Electrochemical reactions appropriate for this situation are suggested; it is pointed out that the proposed mechanism is consistent with the modern theory of corrosion and electrocatalysis.     

Study of the surface layer of ground high strength steels

Grinding is one of the most widely used finishing operations to obtain close tolerances and a reasonably good surface finish. The effects of rough grinding on different types of steels both hardened and unhardened have been studied. Most of the surface defects caused by extremely abusive conditions were produced by rough grinding. The effects of gentle and conventional conditions of grinding were also studied for comparative data.     

高温下石膏的拉曼光谱法研究

利用ALINKAM（TMS94）温度控制系统产生高温,在31℃～301℃温度范围内,对石膏（CaSO4.2H2O）晶体进行了原位高温拉曼光谱法研究。结果表明,在151℃附近,对称性伸缩振动范围属于熟石膏的特征拉曼振动模式（1026cm-1出现）,表明石膏转变成熟石膏（也叫烧石膏）,继续加温至301℃,熟石膏（CaSO4.0.5H2O）的拉曼光谱没有明显变化,熟石膏晶体结构稳定。     

Effect of oxidation on erosive wear behaviour of boiler steels

High efficiency of thermal processes in energy applications is available at high temperatures. The ashes and other components in fluidized-bed boilers act as an erodent particles provoking the competition and interaction between the oxidation and erosion processes. The aim of the study was to investigate the effect of oxidation on the erosive behaviour of boiler steels. Tests were performed using specially developed device allowing testing in either oxidizing or protected atmosphere in a cyclic mode. Several parameters are proposed and the assessment is done on their applicability to describe the erosion–oxidation phenomena under different impact angles. It is shown that under specific conditions oxide scales provide improved wear resistance for some steels, particularly austenitic ones, that enables reduced material losses.