高铬铸铁 High chromium cast iron (中英文对照)

高铬铸铁
High chromium cast iron
高铬铸铁是高铬白口抗磨铸铁的简称，是一种性能优良而受到特别重视的抗磨材料。

它以比合金钢高得多的耐磨性，和比一般白口铸铁高得多的韧性、强度，同时它还兼有良好的抗高温和抗腐蚀性能，加之生产便捷、成本适中，而被誉为当代最优良的抗磨料磨损材料之一。

高铬铸铁属金属耐磨材料、抗磨铸铁类铬系抗磨铸铁的一个重要分支，是继普通白口铸铁、镍硬铸铁而发展起来的第三代白口铸铁。

早在1917年就出现了第一个高铬铸铁专利。

高铬铸铁一般泛指含Cr量在11-30%之间，含C量在2.0-3.6%之间的合金白口铸铁。

High chromium cast iron is of high chromium white cast irons for short, is an excellent performance and highly wear resistant material. Its wear resistance is much higher than the alloy steel, and much higher than the general white cast iron toughness, strength, and it also has good resistance to high temperature and corrosion resistance, and convenient manufacture, low cost, and is regarded as the most excellent abrasive resistant materials.
An important branch of high chromium cast iron metal wear resistant materials, antiwear cast iron chromium wear resistant cast iron, is the third generation of white cast iron after the general white cast iron, Ni hard cast iron and developed. As early as in 1917, the first high chromium cast iron patent. High chromium cast iron generally refers to the content of Cr in 11-30%, C content in 2.0-3.6% alloy white cast iron.
美国高铬铸铁执行标准为ASTMA532M，英国为BS4844，德国为DIN1695，法国为NFA32401。

俄罗斯在前苏联时期曾研制了12-15%Cr、3-5.5%Mn，壁厚达200mm的球磨机衬板，现执行ҐOCT7769标准。

特别值得一提的是在近一个世纪里，曾为抗磨白口铸铁做出了卓越贡献的美国克莱梅克斯（Climax）钼业公司。

1928年该公司首先发明了镍硬铸铁，把抗磨铸铁科技推向了一个空前高度。

1974年为纪念国际GIFA，在杜赛尔多夫展览会上展示了名为“神秘1号”和“神秘2号”。

即经典的高铬抗磨铸铁153（Cr15Mo3）和1521（Cr15Mo2Cu），现如今克莱梅克斯公司执行高铬铸铁标准如下，
The implementation of standards American high chromium cast iron, ASTMA532M, British BS4844, German DIN1695, French NFA32401. Russia in the former Soviet Union had developed 12-15%Cr, 3-5.5%Mn, wall thickness of 200mm ball mill lining board, the executive Ґ OCT7769 standard. It is particularly worth mentioning is in nearly a century, has made the remarkable contribution for the wear resistant white cast iron American clay Mexes (Climax) molybdenum industry company. In 1928 the company invented the first Ni hard cast iron, the abrasion resistant cast iron technology to an unprecedented height. In 1974 to commemorate the international GIFA, in Duesseldorf exhibition called "mysterious No. 1" and "mysterious No. 2". High chromium iron is the classic 153 (Cr15Mo3) and 1521 (Cr15Mo2Cu), now the clay Mexes executive high chromium cast iron standard as follows:
用途: 在采矿、水泥、电力、筑路机械、耐火材料等方面应用十分广泛，常见于衬板，锤头，磨球材质。

Uses: in the mining, cement, electricity, road machinery, refractory material has been widely used, common in the lining plate, hammer, grinding ball material.
高铬铸铁热处理工艺
化学成分:C2.05，Si1.40，Mn0.78，Cr20.03，Ni0.81，Mo0.35常用的高铬铸铁的热处理工艺是加热到950~1000℃，经保温空冷淬火后再进行200~260℃的低温回火。

2、高温团球化处理1140~1180℃保温16h空冷却，可以明显提高冲击韧度和耐磨性能。

高温团球化处理可使碳化物全部呈团球状，可消除或减少大块状和连续网状碳化物对基体的隔裂作用，经团球化的碳化物受到更加均匀的基体支撑，特别受到一定数量的奥氏体的支撑。

如果适当减少保温时间，对薄截面零件也可以取得效果。

该工艺的不足是工艺消耗热能较多。

加热到1050℃，经保温空淬火后再进行550℃的回火,效果会怎么样?要控制加热速度，最好在650 750 850 时保温一定时间。

我以前做过，正火就可以了。

硬度能做到61----65HRC成熟工艺是：铸造后软化退火，便于加工，加工后空冷淬火加低温去应力回火。

使用硬度一般要求为HRC58-62，多用于比如渣浆泵零部件等耐磨易损件。

我们这里是高铬生产基地，一般提供Cr20、Cr24，Cr26，Cr28，Cr15Mo3等，价格是不便宜的。

要包括中间的软化退火和精加后的淬火及回火。

要求硬度HRC>58我们现在用的是淬火液淬火，淬火工艺参数是：650度保温2小时，升温到960度保温3.5小时淬火；回火温度380~400，保温4~6小时。

磨球规格φ40-φ80。

工艺是1050淬火+250~350回火。

Heat treatment of high chromium cast iron
Chemical composition: C2.05, Si1.40, Mn0.78, Cr20.03, Ni0.81, heat treatment process of Mo0.35 common high chromium cast iron is heated to a temperature of 950~1000 ℃, 200~260 ℃low temperature tempering heat air quenched after the. 2, the high temperature spheroidization of 1140~1180 ℃16h air cooling, can significantly improve the impact toughness and wear resistance. High temperature spheroidization of carbides can make all showed nodular, can eliminate or reduce the massive and continuous network of carbon compounds on the substrate cleavage, the spheroidization of carbides was more homogeneous matrix support, particularly by a certain amount of austenite support. If appropriate to reduce the holding time, the thin section parts can also be achieved effect. This process is process consumes more heat. Heated to 1050 ℃, 550 ℃heat air quenching and tempering, the outcome will be? To control the heating speed, the best heat preservation time in 650750850. I have done before, normalizing can. Hardness can do 61----65HRC maturation process is: annealing, softening after casting machining, machining of air cooling after quenching and low temperature stress tempering. The use of hardness of the general requirements for HRC58-62, such as multi for slurry pump parts wearing parts wear. Here is the high chromium production base, generally provide Cr20, Cr24, Cr26, Cr28, Cr15Mo3 and so on, the price is not cheap. To include the quenching and tempering intermediate softening annealing and finishing after. We now use the hardness of HRC>58 is quenched liquid quenching, quenching process parameters are: 650 degrees for 2 hours, up to 960 degree 3.5 hours holding quenching; tempering temperature of 380~400, heat 4~6 hours. Specification of grinding balls of φ 40- φ 80. Process is +250~350 1050 quenching temperin
高铬铸铁生产工艺要点
(1) 高铬铸铁铸造性能较差，其热导率低，塑性差，收缩量大，且有大的热裂和冷裂倾向，在铸造工艺上要将铸钢和铸铁的特点结合起来考虑，必须充分注意铸件的补缩问题，其原则与铸钢件相同( 采用冒口和冷铁，且遵循顺序凝固原理) 。

由于合金中铬含量高，易在铁液表面结膜，所以看起来铁液流动性差，但实际上流动性较好。

(2) 造型宜采用水玻璃硅砂等强度高且透气性好的砂型，涂料应采用耐火度高的高铝粉或镁粉与酒精混合拌制。

另外，为获得细晶粒组织和好的表面质量，在铸件外形不太复杂的情况下，金属型铸造也被广泛采用。

(3) 高铬铸铁的收缩量与铸钢相近，模样制作上其线收缩率可按1. 8 % ～2 % 进行计算。

在砂型制作上，其冒口大小可按碳钢的规定进行计算，而浇注系统则按灰铸铁计算，但需把各截面积增加20 % ～30 % 。

浇冒口的选择应注意两个方面: 一是要保证铸件工作带( 使用部位) 的质量; 二是要尽量提高铸件的成品率。

(4) 由于高铬铸件的冒口不易切除，因此造型时在冒口形式上宜采用侧冒口或易割冒口。

(5) 在具体零件的铸造工艺设计上，要注意不能让铸件出现受阻收缩，以免造成开裂。

另
外，浇注后开箱温度过高也极易造成铸件开裂，540 ℃以下的缓冷是十分必要的，应使铸件在铸型中充分冷却，然后再开箱清砂，或开箱后先勿清砂而堆在一起( 铸件、浇冒系统等) 围干砂缓冷。

开箱周围环境必须保持干燥，不得潮湿有水，否则极易造成铸件裂纹。

(6) 浇注温度要低，有利于细化树枝晶和共晶组织，而且可避免出现因温度过高而造成的收缩过大及表面粘砂等缺陷。

浇注温度一般比其液相线( 1290 ～1350 ℃) 高55 ℃左右，轻小件一般控制在1380 ～1420 ℃，壁厚100mm以上的厚重件控制在1350 ～1400 ℃。

The production process of high chromium cast iron
(1) high chromium cast iron casting performance is poor, its low thermal conductivity, low plasticity, shrinkage, and a large hot crack and cold cracking tendency, will feature a combination of cast steel and cast iron in casting process, full attention must be paid to the problem of feeding the casting, its principle and cast steel parts the same (the risers and chills, and follow the sequence solidification principle). The chromium content in the alloy is high, easy in liquid iron surface film, so the liquid iron poor liquidity, but liquidity is better.
(2) other should use the water glass sand, high strength and good air permeability of sand, paint should be used high refractoriness of high aluminum or magnesium powder and alcohol mixing. In addition, to obtain fine grain microstructure and surface quality of the casting, the shape is not too complex, the metal mold casting is also widely used.
(3) shrinkage of high chromium cast iron and cast steel look similar, making its line shrinkage rate may be 1.8% ~ 2% calculated. In the sand production, the riser size according to the provisions of the calculation of carbon steel, gray cast iron and pouring system according to the calculation, but the cross-sectional area increased by 20% ~ 30%. The riser choice should pay attention to two aspects: one is to ensure casting work belt (position) quality; two is to improve casting yield. (4) due to the high chromium casting riser is not easy to be removed, thus modeling in riser form should use side riser or riser.
(5) in the casting process design of specific parts, be careful not to let the casting has hindered contraction, so as to avoid cracking. In addition, after pouring out of the box temperature also easily cause casting cracking, 540 ℃under slow cooling is very necessary, castings should be sufficient cooling in the mold, and then out of the box cleaning, or out of the box after the first not clear sand heap together (casting, gating and Risering system etc.) in dry sand and slow cooling. Out of the box surrounding environment must be kept dry, not wet water, otherwise easily cause casting crack.
(6) to low pouring temperature, is conducive to the refinement of dendrite and eutectic structure, but also can avoid caused by the high temperature shrinkage is too large and the surface adhering sand defects. Pouring temperature is generally higher than the liquidus (1290 ~ 1350 ℃) high 55 ℃, light a small piece of general control in 1380 ~ 1420 ℃, wall thickness more than 100mm thick piece of control at 1350 ~ 1400 ℃.。