Production and characterization of porous insulating fired clay bricks with corn cobs admixture

Abstract

This research studies physical, mechanical and thermal properties of fired clay bricks. Three different sizes of corn cobs were used as an additional material in production process; large (L) between 2 and 1.7 mm, medium (M) between 1.6 to 1.4 mm and small (S) less than 0.5 mm. Then, they were added into the specimen in an amount of 0, 5, 10, 15, 20, 25 and 30 %wt of the total weight. All samples were fired at 950-1150^oC and were tested by using universal testing machine (UTM), scanning electron microscopy (SEM), specific surface area (BET) and thermal conductivity (heat flow meter). The results indicated that the compressive strength of fired samples clay bricks decreased because of the percentage of corn cobs added in the mixture. However, the specimens with 10 % of large corn cobs which were fired at 1150^oC provided a good result of thermal conductivity. The results also meet the Thai Industrial standard (TIS 77-2545).