铸造用淀粉

加入α淀粉来提高型砂韧性和表面强度：减少起模摩擦力降低水分敏感性， 防止铸件产生加砂、结疤类缺陷和冲砂、砂孔等缺陷： 降低铸件表面粗糙度。随着近几年国外企业以独资和合资的方式进入中国他们的型砂工艺也随之进入 ，这些企业原材料的当地化要求， 推进了中国α淀粉企业发展。α淀粉铸造行业在湿型砂作为附加材料被广泛应用在铸造生产中。 α淀粉在改善型砂松综性能、降低废品率、 提高铸件表面光洁效果显着。

1． α淀粉抗粘砂作用很明显。因而可以代替倍量的煤粉防止粘砂缺陷和降低表面粗糙度，从而改善劳动环境。

2． α淀粉能提高砂型热湿拉强度，砂型表面α淀粉受热燃烧后产生孔隙，能减缓石英砂受热膨胀，从而提高型砂的抗夹砂能力，防止铸件产生夹砂。

3． α淀粉能够降低型砂与模样之间的摩擦阻力提高型砂的韧性、提高型砂起模性，显着减少由于起模不良而出现的型废率。

4． 风干的砂型由于表面失水而致表面强度下降和容易磨损、浇铸时易被冲蚀、放置时间较长或天气较干燥时，问题较严重型砂加入α淀粉能提高砂型表面强度，提高抗风干能力和铁水冲击能力。可防止冲砂、砂眼缺陷。使用α细度较高的淀粉效果更加明显。

5． α淀粉能够显着降低砂型对水分的敏感性，并能减少型砂的水分和提高砂型的紧实率，使砂型更易于造型，大大降低由于砂型水分高引起的气孔缺陷。提高实用性便于造型。

6. α淀粉能降低型砂的高温适度，改善型砂性能。

α 淀粉使用方便，加入量少，一般为在混砂线上按原工艺混合均匀即可。

The addition of starch to improve the toughness and surface strength of sand: reduce mold friction to reduce water sensitivity, and prevent the casting from sanding, scarring and scrubbing, sand holes and other defects: reduce the surface roughness of casting.In recent years, foreign enterprises enter into China in the form of sole proprietorship and joint venture. Their molding sand process also comes into China.In the industry of casting, the wet sand is widely used in casting.It can improve the properties of sand matte, reduce the reject rate and improve the surface finish of castings.

1.The anti - adhesive effect of starch is obvious.Therefore, it can replace the amount of coal powder to prevent the clay sand defect and reduce the surface roughness, thus improving the working environment.

2.It can improve the hot and wet tensile strength of sand mold, and the surface of sand mold can produce pores after burning. It can slow down the expansion of quartz sand under the heat, thus improving the sand retention ability of sand mold and preventing the production of sand inclusion in castings.