1.79萬字             33頁

摘要 鑄造是機(jī)械制造業(yè)的重要組成部分，但是鑄造生產(chǎn)過程中的環(huán)境污染問題非常嚴(yán)重，其中大量使用粘結(jié)劑造成的毒氣、廢氣、廢渣和廢砂問題不容忽視。為了保護(hù)環(huán)境，實(shí)現(xiàn)綠色鑄造，必須對(duì)鑄造用粘結(jié)劑加緊改進(jìn)研究。

常用有機(jī)合成樹脂粘結(jié)劑雖然鑄件質(zhì)量好、強(qiáng)度高，但是其環(huán)境污染及其嚴(yán)重。而無機(jī)水玻璃粘結(jié)劑雖然不污染環(huán)境，但是其潰散性不佳和舊砂再生問題不好解決。因此，這兩種粘結(jié)劑都算不上是綠色鑄造粘結(jié)劑。另一種無機(jī)粘結(jié)劑——基于磷酸鹽的粘結(jié)劑經(jīng)研究表現(xiàn)出良好的潰散性和高溫性能，所以是很有發(fā)展?jié)摿Φ男滦途G色鑄造粘結(jié)劑。

影響磷酸鹽粘結(jié)劑用于鑄造生產(chǎn)的最大難題是它的抗吸濕性差。前期研究表明加入PVA可以有效改善鋁磷酸鹽的抗吸濕性，并制備出此種改性粘結(jié)劑。本課題于明志科技公司的裝備現(xiàn)場(chǎng)對(duì)這種改性粘結(jié)劑進(jìn)行生產(chǎn)工藝性研究，觀察它在鑄造車間制芯時(shí)表現(xiàn)出的工藝性能。

結(jié)果表明改變混砂順序能夠改變流動(dòng)性和抗吸濕性，也會(huì)使得強(qiáng)度有所改變。由于射砂模具、加熱方法的不足以及射砂、吹氣參數(shù)的不同，砂芯出現(xiàn)一些疏松、裂紋及未固化現(xiàn)象，說明改進(jìn)模具設(shè)備、優(yōu)化固化工藝也是提高粘結(jié)劑抗吸濕性的有效途徑。

關(guān)鍵詞 鑄造粘結(jié)劑 磷酸鹽 流動(dòng)性 抗吸濕性 熱固化

 

Process Research of a Clean Foundry Binder

Abstract Foundry is an important part of the machinery manufacturing, however, the environmental pollution problem during the foundry production process is very serious, of which the poison gas, waste gas, waste residue and waste sand problems resulting from the extensive use of casting binders cannot be ignored. In order to protect the environment, to realize green casting, foundry binder must be stepped up efforts to improve research.

Although common organic synthetic resin binder castings are of good quality, high strength, environmental pollution is really serious. Although inorganic sodium silicate binder does not pollute the environment, but its collapsibility and sand reclamation problem is hard to solve. Therefore, both of them are no green casting binder. Another inorganic binder, based on phosphate binder studies showed good collapsibility and high temperature performance, so is of great potential for development of new green casting binder.

One of the biggest hurdles that affect phosphate binder used for casting production is its poor resistance to moisture absorption. Early research suggested that adding PVA can effectively improve the moisture resistance of aluminum phosphate, and this modified binder were prepared. In this paper, production technology for this modified binder was tried in workshop of MingZhi Company, to observe its process properties in core making.

Experimental results showed that the sand preparation process changed flowability, moisture resistance and strength. Due to the shortage of core-box and the heating method as well as the difference of core shooting and blowing parameters, some loose, crack and no curing phenomenon were appeared, which meant that improvement of mold equipment, optimization of solidification process would be effective ways to improve the adhesive resistance to moisture absorption.

Key words  foundry binder  phosphate  fluidity  moisture resistance  heat curing