铸铁--硬质合金的复合铸造

用砂型铸造型法研制了铸铁－硬质合金复合铸造工艺，铸件界面结合强度达到757MPa，铸铁－硬质合金界面区域由4层组成，依次为铸铁层，混合层，扩散层和硬质合金层。二者的冶金结合是通过铸铁液将硬质合金表层熔融，然后混合凝固获得的。断裂裂纹主要产生在界面区域的铸铁层内。     

中国超硬材料发展30年(续)——纪念我国人造金刚石诞生30周年

2.2.7 超硬材料硬质合金复合片的研制 1980年以来,第六砂轮厂开展了超硬材料复合片的研制与应用工作,定型了三种立方氮化硼复合片(牌号DLS—F_1、DLF—F_2、KLS—F_3),刀具规格由φ9.5～φ12mm。它们适宜加工的对象是:DLS—F_1加工各种淬火钢、冷硬铸铁;DLS—F_2宜加工各种冷硬铸铁;DLS—F_3宜加工耐热合金、钛合金。定型的金     

冷硬轧辊辊面的加工

本文介绍了采用硬质合金H19及复合陶瓷刀片,加工硬度HS72-78的冷硬复合铸铁轧辊的经验,可供有关技术人员参考。     

煤矿工业用耐磨复合材料的制备与性能研究

针对采用整层复合的陶瓷增强铁基表层复合材料存在的复合层易开裂、剥落的问题,提出采用局域化增强结构的设计方案,制备了钴基硬质合金局域化增强高铬铸铁铁基表层复合材料,并对复合材料的组织、界面、磨损性能和磨损机理进行了研究。结果表明:该复合材料具有增韧效果较好,裂纹不易扩展,增强区域分布均匀等优点;钴基硬质合金/高铬铸铁复合材料相对耐磨性是基体材料的8.24倍,具有优异的耐磨性。随着磨损阶段的进行,复合材料的磨损率下降更为明显,反映了高硬度硬质合金在磨损后期充分发挥了抗磨作用。磨粒磨损过程中,复合材料组织中硬质合金增强区域凸出于高铬铸铁基体,且其间具有良好的冶金结合界面,因此增强体保护基体材料和基体材料支撑增强体的协同效应使复合材料具有了优越的耐磨性。     

复合轧钢机导卫板的研制

在总结了导卫板的失效形式和硬质合金的性能特点基础上,提出了用硬质合金制作导卫板,为提高硬质合金导卫板的抗断裂能力和降低生产成本,开发了硬质合金导卫板复合铸造工艺。结果表明,应用复合铸造工艺生产的导卫板使用安全、可靠;使用效果明显优于常用高镍铬钢导卫板和高铬铸铁（钢）导卫板;使用复合导卫板后,轧材精度高、表面质量好、生产线开工率提高２％～４％,具有良好的经济和社会效益,值得广泛推广使用。     

硬质合金在热轧技术中的应用

为适应热轧生产中的不同要求，研制出日前具有最高和最低粘结相的硬质合金轧辊，并开发出铸入式复合硬质合金（ＣＩＣ）专利技术，可用于线材、棒材、钢管的生产中，各种硬质合金辊的寿命是普通铸铁辊的２０倍以上。     

Cr26高铬铸铁-硬质合金复合耐磨溜槽衬板

Cr26高铬铸铁-硬质合金复合耐磨溜槽衬板,冶金结合良好,无内部组织缺陷。基体宏观硬度HRC≥60,aK≥6 J/cm2,硬质合金复合前后的硬度无明显变化。比传统的堆焊、钎焊镶嵌硬质合金复合铸造等,更具有优异性能。以Mo、W、V、Ti等多元合金化形成的超硬韧M基体和具有超强抗磨性及一定耐热耐腐蚀性的W-Co硬质合金的冶金结合,二者的协同性,使复合技术效果发挥极致,实现了耐磨损复合材料技术的新突破。工业应用实践表明十分抗磨,极具理论研究和工程应用价值。     

硬质合金轧辊在轧钢生产中的应用

为了满足用户对轧辊寿命和性能不断提高的要求 ,研制了含有较高和较低粘结相的硬质合金轧辊 ,并开发出复合硬质合金 (CIC)专利技术 ,应用于棒材、线材、无缝钢管及其他小型材生产 ,不仅具有良好的可加工性 ,而且寿命是普通铸铁轧辊的 2 0倍以上     

复合涂层刀具加工RuT500的铣削力研究及参数优化

为探究和改善蠕墨铸铁RuT500的铣削力，基于单因素试验，选用TiAlN/AlCrN、TiCN/Al₂O₃复合涂层硬质合金刀具对RuT500进行铣削加工，结合响应面探究涂层和铣削参数对RuT500铣削力的影响规律，并进行了铣削参数优化。结果表明：相比于TiAlN/AlCrN复合涂层硬质合金刀具，TiCN/Al₂O₃复合涂层硬质合金刀具铣削RuT500时会产生更大的铣削力；对蠕墨铸铁铣削力影响最显著的因素是背吃刀量，其次是进给量，铣削速度对蠕墨铸铁铣削力的影响程度相对较少；铣削参数交互作用对铣削力的影响具有一定的显著性；取较大的背吃刀量a_p、适当的进给量f和较大的铣削速度v_c时，可以获得较低的铣削力F和良好的加工效率。     

介绍一种HTS—C新颖复合钻

HTS-C复合钻由导向钻头、装硬质合金可转位刀片的刀头和开有螺旋槽的刀杆组成。这种复合钻适用于钻削钢、铸铁和铝等实心材料,钻孔深度可达8×dmm,加工孔径     

Microstructure and Wear Behavior of High-Cr WCI Matrix Surface Composite Reinforced with Cemented Carbide Rods

The present article reports a new superior wear resistance surface composite prepared by a vacuum evaporative pattern casting-in process. This surface composite was constructed with reinforcing cemented carbide rod (CCR) array within high-Cr white cast iron (WCI) matrix. Three reaction zones that formed around the CCRs were characterized and established the good metallurgical bonding between CCRs and matrix. In addition, some compound carbide containing Fe, Cr, W, and Co elements were formed in the reaction zones, owing to the partial dissolution of the CCRs and the resulting interdiffusion of elements such as W, Co, C, Fe, and Cr. The wear behavior of the composite was evaluated and compared with unreinforced high-Cr WCI by means of a three-body abrasive wear tester. The results showed that the wear resistance of the composite was significantly higher than that of the unreinforced high-Cr WCI. The exciting wear resistance can be ascribed to protective effect introduced by the CCRs during wear process and the good metallurgical bonding between CCRs and matrix.     

固-液复合铸造锤头的组织与性能

研究高铬铸铁-碳钢固-液复合铸造锤头的组织及硬度分布特征。结果表明,固-液复合铸造高铬铸铁锤头部分具有较高的硬度,远离复合面高铬铸铁硬度增加,碳钢硬度降低。远离复合面高铬铸铁组织为M7C3型碳化物+回火马氏体+残余奥氏体,固-液复合铸造高铬铸铁组织中碳化物有定向分布的趋势,有利于提高锤头的耐磨性;远离复合面碳钢部分的组织为珠光体和较多的铁素体,复合面附近碳钢组织珠光体数量明显增加,铁素体数量明显减小,高铬铸铁中的碳通过复合界面向碳钢进行扩散。     

Preparation of in situ-formed WC/Fe composite on gray cast iron substrate by a centrifugal casting process

An iron-based composite reinforced by in situ-formed tungsten carbide particles was fabricated on gray cast iron substrate by a centrifugal casting process. The as-prepared composite was characterized by X-ray diffraction, scanning electron microscopy, and microhardness and wear testers. An appropriate pouring temperature (1300 °C) of the gray cast iron melt was chosen considering the dissolution temperature of the tungsten wires determined by differential scanning calorimetry. The experimental results showed that the tungsten wires were dissolved partially by the cast iron melt. As a result, primary and secondary tungsten carbide particles and pearlite with a negligible amount of graphite flakes were formed as the reinforcing phase and the matrix, respectively. The composite with a thickness of about 3 mm was dense and metallurgically bonded to the gray cast iron substrate. Wear resistance was determined by a pin-on-disc wear test technique, indicating that the composite containing high volume fraction of hard tungsten carbides presented higher wear resistance compared with the unreinforced gray cast iron.     

深冷处理对硬质合金直槽钻切削寿命的影响

深冷处理硬质合金,能够提高硬质合金的韧性、疲劳强度和耐磨性。通过三组直槽钻头,在同一加工参数下加工同一种铸铁材料。分析了各个刀具的磨损情况,并判断刀具的耐用度。结果表明:经过涂层且深冷处理过的直槽钻头耐用度最好。     

Shielded metal arc welding of cemented carbide to carbon steel

Electrode ENiFe-C1 and E4303 were selected to join the cemented carbide WC-20Co and carbon steel 45 by shielded metal arc welding process. Microstructure and bending property of the corresponding joints were analyzed. The results showed that the carbon steel electrode E4303 had no proper metallurgy condition for the arc welding of cemented carbide and carbon steel. The C and Ni content of the cast iron electrode ENiFe-C1 could meet the condition of preventing the formation ofη carbide,which was suit to the arc welding of cemented carbide and carbon steel,but the operation parameters needed to be optimized to minimize the slag inclusion. The alloy WC-20Co which did not fit for cold arc welding,by adopting the measure of being preheated at 723 K for 1 h before welding,and being kept at 723 K for 3 h after welding then followed furnace cooling could avoid the happening of crack in the WC-20Co base metal.     

冷硬铸铁轧辊成型硬质合金铣刀的研究

热轧花纹板的冷硬铸铁轧辊表面密布半圆形槽腔，是典型的难加工零件，此文介绍了采用硬质合金铣刀进行切削加工的成功经验。     

Cutting performance improvement of MTCVD coated cemented carbide inserts via appropriate heat treatment

The softening of cemented carbide at the elevated temperature of MTCVD processes results in significant reduction of their strength, and thus, high coating deformation during cutting. In this way, at interrupted cutting loads, as during turning cast iron, the cutting performance of MTCVD coated cemented carbide inserts degrades due to premature coating fatigue fracture. To overcome this problem, appropriate heat treatments of MTCVD coated inserts were conducted. The related temperatures and durations for improving the substrate properties were optimized considering obtained strength data of uncoated inserts variously heat treated and the turning performance of coated ones correspondingly heat treated.     

含钨白口铸铁共晶碳化物团球化研究

研究了Ce、K、Na复合变质处理对含钨白口铸铁组织和性能的影响,提出了评价碳化物变质效果的圆度概念,并讨论了共晶碳化物团球化对力学性能和耐磨性能的影响。变质处理后,由于共晶碳化物形态的改善,含钨白口铸铁的力学性能,尤其是冲击韧性大幅度提高,抗冲击磨损性能也显著提高。经变质处理的含钨白口铸铁轧辊使用寿命比高铬铸铁轧辊提高20%以上,生产成本降低30%以上。     

硬质合金复合材料

一种由硬质合金基体和硬质合金粒子制成的硬质合金复合材料。硬质合金表面均匀地分布一层高于基体硬度的粒子,这种复合材料具有表面高耐磨性,中心高韧性的特点。     

Effects of RE,V, Ti and B composite modification on the microstructure and properties of high chromium cast iron containing 3% molybdenum

The effects of RE, V, Ti and B on the microstructure and properties of high chromium cast iron containing 3% molybdenum under as-cast and heat treatment conditions were investigated with the method of comparing experiments. The results show that with the increase of RE content, the primary austenite of high chromium cast iron is obviously refined. The morphology of carbide is changed from netlike and lath to small multiangular isolated blocks or massive blocks, the isolated degree of carbide is improved obviously, and the size is significantly refined. The addition of V and B into high chromium cast iron can refine the microstructure, reduce coarse columnar crystals and make the carbide smaller and uniform. Through composite modification with RE, V, Ti and B, the hardness, wear resistance and impact toughness of high chromium cast iron are increased conspicuously. After heat treatment, the hardness of high chromium iron is increased significantly, but the toughness and wear resistance do not show great improvement.