本文關(guān)鍵詞： 雙金屬 液液復(fù)合 耐磨性 錘頭 冶金結(jié)合　出處：《河南科技大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：錘式破碎機(jī)廣泛應(yīng)用于礦山、水泥、冶金、電力、耐火材料、玻璃及化工等行業(yè)破碎物料,錘頭(或板錘)的磨損十分嚴(yán)重,少則數(shù)天,多則數(shù)月便要更換一幅錘頭,造成大量的人力物力的浪費(fèi),因此提高錘頭的耐磨壽命受到用戶的普遍關(guān)注。本論文研究開發(fā)了雙金屬液液復(fù)合技術(shù),應(yīng)用于高耐磨、較高韌性和低成本的耐磨產(chǎn)品的鑄造生產(chǎn),不僅保證了錘頭良好的耐磨性,又大幅度提高了錘頭的抗沖擊能力。采用砂型鑄造方法生產(chǎn)液-液雙金屬復(fù)合錘頭和板錘,耐磨層采用高鉻鑄鐵Cr20,墊層采用具有高強(qiáng)韌性的35CrMo低合金鋼。錘頭復(fù)合工藝鑄造時(shí),錘柄朝下,錘頭朝上,先定量澆注低合金鋼錘柄,經(jīng)過適當(dāng)?shù)耐Ａ艉笤贊沧⒏咩t鑄鐵耐磨層,兩層金屬之間實(shí)現(xiàn)良好的冶金結(jié)合。板錘復(fù)合工藝鑄造時(shí),板錘的兩個(gè)耐磨面朝外,分三層澆注,最下邊一層是高鉻鑄鐵耐磨層,第二層是低合金鋼墊層,最上邊一層是高鉻鑄鐵耐磨層,三層依次定量定時(shí)澆入,各層之間形成良好的冶金結(jié)合。兩種金屬液均采取變質(zhì)處理,一方面改善高鉻鑄鐵的碳化物形態(tài)與分布;另一方面細(xì)化低合金鋼的晶粒度,防止低合金鋼在高溫?zé)崽幚頃r(shí)晶粒過分長大。液液復(fù)合錘頭采用加熱到950-980℃,然后空冷的熱處理工藝,使耐磨層處于淬火狀態(tài),具有高硬度、高耐磨性;使背層處于正火狀態(tài),保持足夠的強(qiáng)韌性。復(fù)合錘頭的主要技術(shù)指標(biāo)如下:(1)高鉻鑄鐵耐磨部位硬度HRC≥58,韌性ak≥7J/cm2。(2)雙金屬復(fù)合體的耐磨性和使用壽命是高錳鋼的2.5-5倍。比整體高鉻鑄鐵錘頭的韌性高,成本低。雙金屬液-液復(fù)合錘頭的創(chuàng)新性主要體現(xiàn)在:(1)采用無箱組芯造型工藝鑄造復(fù)合錘頭,生產(chǎn)效率高,可操作性強(qiáng);(2)板錘率先采用了雙液三次澆注復(fù)合工藝,突破了板錘難以復(fù)合的技術(shù)難題;(3)復(fù)合板錘采用兩種金屬共用一個(gè)澆道新工藝。創(chuàng)新了錘頭的雙液澆注,促使復(fù)合錘頭的質(zhì)量有了進(jìn)一步提高;(4)兩種金屬實(shí)現(xiàn)了良好的冶金結(jié)合,界面強(qiáng)度高,是液固復(fù)合的1.3-1.5倍;(5)大幅度降低貴重金屬消耗,降低生產(chǎn)成本約30%左右。
[Abstract]:Hammer crusher is widely used in mining, cement, metallurgy, electric power, refractory, glass and chemical industries. The wear of hammer head (or plate hammer) is very serious. In a few days or months, a hammer head needs to be replaced. This paper studies and develops the bimetallic liquid liquid composite technology, which is applied to high wear resistance. The casting production of wear-resistant products with high toughness and low cost not only ensures the good wear resistance of the hammer, but also greatly improves the impact resistance of the hammer. The wear resistant layer is made of high chromium cast iron Cr20, and the cushion layer is 35CrMo low alloy steel with high strength and toughness. After a proper stay, the wear resistant layer of high chromium cast iron is poured, and a good metallurgical combination is realized between the two layers of metal. During the casting of the plate hammer composite process, the two wear-resistant surfaces of the plate hammer are cast outwards, divided into three layers, and the lowest layer is a wear-resistant layer of high chromium cast iron. The second layer is low alloy steel cushion, the top layer is high chromium cast iron wear-resistant layer, three layers are poured in quantitatively and regularly, and good metallurgical combination is formed between each layer. Both kinds of molten metal are modified. On the one hand, the carbides morphology and distribution of high chromium cast iron are improved; on the other hand, the grain size of low alloy steel is refined to prevent it from overgrowing during high temperature heat treatment. The liquid-liquid composite hammer is heated to 950-980 鈩，

本文編號：1554069