高铬铸铁衬板的耐磨性研究

分析3种不同形态碳化物与基体组织分布的高铬铸铁衬板,在MM-W1A型摩擦磨损试验机上与沙石进行耐磨性对比。结果表明:碳化物形态分布对高铬铸铁耐磨性有直接的影响,块状或短杆状且分布均匀的碳化物对提高材料的耐磨性有利,网状或长针状碳化物对耐磨性不利。     

立轴锤式破碎机衬板的研制

根据立轴锤式破碎机的工作情况,对该机衬板的失效形式的分析,认为商铬铸铁可以作为衬板的材料,介绍了该衬板铸造工艺及热处理的方法。通过工业性试验表明,高铬铸铁衬板的使用寿命是高锰钢衬板的2-3倍,具有良好的经济效益。     

高铬铸铁后衬板铸造工艺的优化设计

2010年我公司接到一个生产高铬铸铁后衬板备件的项目。后衬板毛坯三维结构如图1所示,最大直径1444mm,高76mm,内孔直径964mm,单面加工余量8mm,铸件重1100kg。材质为高铬铸铁,产品技术要求十分严格,加工面不允许有任何铸造缺陷。     

微量钒,钛对稀土中锰白口铸铁组织和性能的影响

本文介绍了微量钒、钛能使稀土中锰白口铸铁组织细化,硬度略有提高,动态断裂韧性提高39.4％,抗磨损性提高74 2％。经生产表明,含钒、钛的稀土中锰白口铸铁衬板寿命提高2～3倍。     

一种混凝土湿喷机衬板材料的研究及应用

本文设计出耐磨合金铸钢衬板化学成分和制造工艺，并与高铬铸铁衬板试样进行硬度、耐磨性、韧性、金相对比试验，结果表明，该耐磨合金铸钢综合性能达到设计指标，具有应用价值。     

钒在高铬铸铁中的作用

本文研究钒对高铬铸铁组织和性能的影响。试验结果表:在高铬铸铁中加入0.2～0.5%V 能改善组织并提高其综合机械性能。     

高铬耐磨铸铁锤头和衬板在锤式破碎机上的应用

从分析锤式破碎机锤头和衬板的工作条件出发，论证了采用高铬耐磨铸铁的合理性；介绍了锤头和衬板化学成分的选择。熔炼、铸造和热处理工艺，可作为同类型产品或材料在制造过程中的参考。     

延长衬板寿命的方法

我公司2500m~3高炉上料系统采用双机带式运输机传送,在其转运站中,采用翻板4实现运料从一条输送带2向另一条输送带转运(图1)。翻板4上安装衬板5。烧结矿从上一层输送带经漏斗收集后,直接落在衬板5上,落差2m。对衬板5造成强烈冲击。衬板5磨损严重,试用多种耐磨材料,效果均不理想。用我厂专门试制的高铬铸铁衬板,kmT-BCr15Mo2DT(厂内牌号)也仅用20天左右即报废,这不到60天的设计寿命。经过试验,我选用高铬铸铁为材料,将原设计的平面型材板改为L形(见图2)。给衬板增加一个直角边,根据衬板的工作位置,取H=     

高铬铸铁叶片材质研究

对高铬铸铁叶片材质进行了系统的实验室研究和装机试验,确定了碳和铬对相结构、组织、力学性能和耐磨性能的影响及其相互关系,得出较佳的高铬铸铁成分,所制成叶片使用寿命比原中铬铸铁、高碳高铬铸铁提高6倍。     

稀土高铬铸铁热处理工艺的改进

众所周知,高铬铸铁具有较高的硬度和一定的冲击韧性,因此,它已成功地应用在冶金、建材、电力等行业中,但因存在着易脆裂的缺陷,故限制了使用范围。用稀土元素对高铬铸铁进行变质处理,并进行合适的热处理,可使这种铸铁的冲击韧性和硬度提高。我们首先进行实验室试验,即用50kg电炉熔炼,试样由同炉稀土高铬铸铁铁水浇注而成,其尺寸为20×20×110mm无缺口方形,化学成分见表1。然后进行生产性试验,用0.5t碱性电弧炉进行冶炼,试样与衬板铸件连在     

高铬铸铁可锻性及锻后机械性能

通过高铬铸铁热塑性变形试验得知,在奥氏体化温度范围内,高铬铸铁具有良好的塑性变形能力。经塑性变形后,其大块共晶碳化物被破碎,并在本体中均匀分布,减少或消除了铸造缺陷,提高了机械性能,尤其是冲击韧性的提高更为明显。还提出,经等温淬火后,可获得良好的综合机械性能。     

MPS（MBF）型中速磨煤机用高铬白口铸铁磨辊的研制

在分析ＭＰＳ（ＭＢＦ）型中速磨煤机用磨辊的工况条件和性能要求的基础上，结合国内资源，设计确定了材料的成分组成，制定了合理的铸造、热处理工艺，成功地研制了适合我国煤质特点的高铬白口铸铁磨辊．试验运行结果表明，同样工况条件下，所研制的高铬白口铸铁磨辊的耐磨寿命比进口镍硬Ｎ＃铸铁提高５０％以上，且成本降低，经济效益十分可观．     

Abrasive wear resistance of spheroidal vanadium carbide cast irons

The effect of the chemical composition and heat treatment on the microstructure and abrasive wear resistance of V-Mn, V-Ni-Cr, and V-Mo spheroidal vanadium carbide cast irons (18–23 vol %) has been studied. The wear resistance has been determined under conditions of wear by abrasives with various hardnesses, i.e., corundum and quartz and compared to that of high-chromium cast iron with 13% Cr. It has been found that the advisability of using high-vanadium cast irons is governed by the hardness of the abrasive. When a hard abrasive, i.e., corundum was used, V-Mo cast iron with the maximum concentration of spheroidal VC carbides, which were uniformly distributed in the martensitic matrix, had the highest wear resistance. When a soft abrasive, i.e., quartz, was applied, high-chromium cast iron with a hardness of 68 HRC, which contained the largest amount of M₇C₃ carbides, was more wear-resistant. In the course of isothermal exposure at 300–1000°C, V-Ni-Cr and V-Mo cast irons with an austenitic structure had high resistance to phase and structural transformations. However, the properties and microstructure of V-Mo cast irons with a martensitic matrix depended strongly on the temperature of exposure during heat treatment.     

包覆对称组坯热轧制备高铬铸铁/低碳钢耐磨复合板

通过对碳钢板和高铬铸铁板进行六层对称包覆组坯,在1 200 ℃下分别采用30%和60%压下率多道次热轧制备了耐磨复合板。使用扫描电镜对试样的微观组织和界面结合情况进行了观察。试验结果表明：热轧后板形表现平直无翘曲现象;热轧过程中较软碳钢层的协调变形和应力释放作用使得高铬铸铁热变形裂纹敏感度降低,脆性高铬铸铁层实现了一定程度的热变形;两种材质界面结合质量良好,无可辨别的沿界面的夹层和空隙等缺陷;通过EDS能谱检测发现在高铬铸铁侧有无碳化物的过渡区,界面两侧的硬度值连续变化,证明两种材料实现了冶金结合。     

灰铸铁表面原位合成TiC/Al3Ti复合涂层的组织及耐磨性

采用铸造反应合成技术在灰铸铁表面原位合成TiC/Al3Ti复合涂层材料,对复合涂层的显微组织、硬度和耐磨性进行了研究。结果表明:Al-Ti-C体系完全反应后可制备出纯净的TiC/Al3Ti表面复合涂层材料,该表面复合材料组织致密,并随着涂层中TiC含量的增加,材料的硬度有所提高,表面复合涂层的硬度明显高于铁基体的硬度,磨损性能也要优于铁基体,明显改善了铸铁的表面硬度和摩擦性能。       

锰硼奥氏体基高铬铸铁的组织结构及抗磨性研究

研究了四种不同含B量的Fe-Cr-Mn-C-B系铸造合金的铸态组织结构及摩擦磨损特性。结果表明：硼碳化物体积分数随B含量增加而增大，并可按等量原子比估算。由于含B合金基体表面更易摩擦诱发马氏体相变，且产生表面细晶强化作用，显著提高了滑动磨损的抗磨性。含硼0．3％时，滑动磨损的抗磨性是25Cr马氏体基合金的4倍，是Mnl3铸钢的7．6倍。     

Effect of Carbides on Wear Characterization of High-Alloy Steels under High-Stress Rolling–Sliding Condition

This article describes the wear characterizations of high-speed steel composed of vanadium carbide and high-chromium cast iron composed of chromium carbide. These metals were studied under rolling–sliding conditions with a sliding ratio of 10% using a self-made ring–ring wear testing machine. The fine microstructure of carbides and failure behaviors were analyzed by scanning electron microscopy and high-resolution electron microscopy. The results showed that carbide significantly affected the wear properties and failure behaviors of metals. The relative wear resistance of high-speed steel reinforced by vanadium carbides was twice that of high chromium cast iron composed of chromium carbides. Chromium carbide was characterized by a stacking fault substructure, and slips occurred in chromium carbide under high-stress contact, resulting in crack formation. Vanadium carbide was reinforced and pinned by large amounts of nanoparticles, which prevented its dislocation under high-stress rolling–sliding conditions, thereby effectively resisting crack initiation. Furthermore, the (200) lattice plane of vanadium carbide is coherent with the (111) lattice plane of austenite, preventing cracks from forming at the interface of the vanadium–carbide matrix. The morphology and hardness of vanadium carbide also contributed to the excellent wear property of high-speed steel.     

Effect of Carbide Orientation on Impact-Abrasive Wear Resistance of High-Cr Iron Used in Shot Blast Machine

In this work, the blades of shot-blasting machine were fabricated by high-chromium cast irons using investment cast processing to control different cooled rate in order to achieve solidification unidirectionally. The microstructure of oriented M₇C₃ carbides was simulated and revealed using deep itching methods. The rod-like M₇C₃ carbides in longitudinal direction and lath-shaped M₇C₃ carbides in transverse and vertical direction are observed. When the long axis of the carbide rods is paralleling to the shots flow direction, high-chromium cast irons possess higher hardness and fracture toughness than that of perpendicular to the shots flow direction. The results reveal that the blades possessing oriented M₇C₃ carbides in longitudinal direction exhibit excellent impact-abrasive wear resistance than that of in transverse and vertical direction. The wear surface was examined by scanning electron microscopy for identifying the impact wear mechanisms.     

合金元素对室温油分级等温淬火贝氏体球铁组织和性能的影响

采用一种新的室温油分级等温淬火工艺获得低合金贝氏体球墨铸铁;研究了硼、铜、锰对贝氏体球墨铸铁组织和性能的影响,并讨论了球墨铸铁的性能滞后现象,即等温淬火后随时问延长硬度增加的现象。结果表明：硼和锰能提高硬度,降低韧性;铜提高韧性。合理加入合金元素有利于提高贝氏体球铁的性能。贝氏体球墨铸铁有性能滞后现象,其实质是溶质类拖曳作用。     

优化合金元素加入量对蠕墨铸铁耐磨性的影响

通过设计合金元素锑、硼、磷加入量的三因素、二水平的正交试验,研究了合金元素及其加入量对蠕墨铸铁的蠕化率、基体组织、硬度和耐磨性的影响。优选出了合金元素的加入量为：0．03％Sb,0．03％B,0．25％P,并对新材料进行了模拟磨损试验。结果表明：新研制的低合金蠕墨铸铁比铬钼铜硼磷灰铸铁的综合相对耐磨性提高17．56％,而生产成本有所降低。