The Research of the Aging Treatment on the Properties of Standard Test Specimen of the Green Sand and Their Predictions

• Main Authors: Wu, Jonq-jyh, 吳仲志
• Other Authors: Yang Rong-Shean
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/23656520033870043080

碩士 === 逢甲大學 === 機械工程研究所 === 84 === ABSTRACT The green sand molding process is one of the molding processes which has long- standing history from ancient to now. Following the progress of the time , this molding process is not excluded .And this process can be more useful in castingbecause the new molding machine is been developing and using. The major reasonsin this process is still widely used are easy molding,high productivity, lowcost,recyclic use of the sand,etc. To the Green Sand Molding Process , the properties of molding sand will directly affect the quality of casting after poured.In general , the methods of improving the molding sand properties are (1)by adding additives to the moldingsand , (2)increasing the squeeze pressure of molding ,(3)using the molding sandwhich is treated by .various aging type.But the third method using age treatmenthas lost cost and best effect . Treatment method is adopted by some foundry factory . However,the research concerns with the effect of age treatment on theproperties of molding sand is very limited. This study was constructed in the condition that silica sand , bentonite ,additives and water were at fixed composition . The mixing was made under theselection of different aging type , and time . Then we make the standard testspecimen of green sand mold by squeezer and rammer,The objective is to find theefff different aging type( Full Aging,After Aging,Pre Aging),and aging time(1,3,5,7hr...... etc)to the properties (wet compression strength , permeability, compression ratio , surface stability index) of standard test specimen of green sand mold,and use SEM to observe the bonding condition of silica sand,bentoniteand water in molding sand. In addition to that , by using the second order multiple regression model to establish the quantitative adjustment model on the green sand properties , thento insure the stability of the green sand properties, and providing the methodthat to predict the relations among the properties.