The objective of this research is to develop the high corrosion resistance and good thermal insulation precast adobe wall panels mixed with natural latex. The 6 ratios of Portland cement type1: clay: rice husk ash: straw: rice husk:waterproofed liquid: natural latex: tap water were designed including: 1: 3: 0.3:0.02: 0.02: 0.02: 0: 0.4 1: 3: 0.3: 0.02: 0.02: 0.02: 0.05: 0.4 1: 3: 0.3: 0.02: 0.02: 0.02:0.1: 0.4 1: 3: 0.3: 0.02: 0.02: 0.02: 0.15: 0.4 1: 3: 0.3: 0.02: 0.02: 0.02: 0.2: 0.4 and 1:3: 0.3: 0.02: 0.02: 0.02: 0.25: 0.4 by weight. The precast adobe wall panels castedas same as the common concrete and reinforced by the bamboo. From the resultsthe proper ratio of precast adobe wall panel mixed with natural latex was 1: 3: 0.3:0.02: 0.02: 0.02: 0.1: 0.4 ratio. The properties of the proper precast adobe wall panelincluded density 1810.83 kg/m3 water absorption 17.16 % compressive strength 15.13MPa bending strength 3.01 MPa thermal conductivity coefficient 0.234 watt/m.Kelvin. Moreover the proper precast adobe wall panel mixed with natural latex also was verified by TIS.2226-2548 with properties of impact resistance deflection and hardness in medium duty (MD) level. The proper amount of natural latex effected the precast adobe wall panels to improve the mechanical properties including: increase the compressive and tensile strength decrease the density thermal conductivity coefficient and water absorption.

The objective of this research is to develop the precast adobe wall panel with high corrosion resistance and good thermal insulation. The ratio of Portland cement type1 clay rice husk ash straw rice husk waterproofed liquid and tap water was mixed and casted as same as the common concrete and reinforced by bamboo. From the results the proper prototype ratio of precast adobe wall panel was Portland cement type1: clay: rice husk ash: straw: rice husk: waterproofed liquid: tap water which equal to 1: 3: 0.3: 0.02: 0.02: 0.02: 0.4 by weight. The properties of the precast adobe wall panel prototype included density 1797 kg/m3 water absorption 16.70% bending strength 2.61 MPa compressive strength 21.40 MPa thermal conductivity coefficient 0.314 watt/m.Kelvin. Moreover the precast adobe wall panel prototype also was verified by TIS.2226-2548 with properties of impact resistance deflection and hardness in medium duty (MD) level. These straw and rice husk effected the precast adobe wall panel to decrease the density bending strength thermal conductivity coefficient and increase the compressive strength and water absorption.

Molds manufacturing to produce chloroprene rubber product with carbon steel over time the mold surface will wear. From the original. The practice in the industry often uses surface coatings (Hard chrome method) or change materials to create molds. Therefore this research is to study the effect of corrosion or wear. To see the size of surface mold changed in the experiment. Based on a tolerance of 0.1 millimeters at the molding point and after molding in the actual work conditions of a 2-3 weeks sample and mold size measurement. At less than 10 times the permissible coordinate value is 0.01 millimeters. The experiment found that. The wear of carbon steel molds was formed with chloroprene rubber. It has a very small value when referenced to the tolerance coordinates which is not significantly reduced when the rubber specimen size is determined. The allowance range is 10 μm to 100 μm. Therefore the design of chloroprene rubber to make molds with carbon steel. It can help reduce production costs. Without replacing with corrosion-resistant materials or adding coatings.

After a propeller shaft was damaged from chloride in sea water it has been fixed by MAG welding process with flux cored wire. Its service life after welded depends on the corrosion resistance of the weld metal. This research aimed to compare the corrosion resistance of two different weld metals between X111-T5-K4 and E71T-1CH8/T/9M-D flux core wire. The test specimens were prepared according to the ASTM G1-103 standard and tested by salt spray test conforming to the ASTM B 117 standard. The result of the test showed that the corrosion rate of the weld metal using X111-T5-K4 flux cored wire is lower than the weld metal of E71T-1CH8/T/9M-D flux cored wire which was 0.21 and 0.32 mm2/hr. respectively. The mass loss at 24 hours of E71T-1CH8/T/9M-D X111-T5-K4 flux core wire were 0.32 and 0.48 grams respectively. Therefore enhancing the service life of propeller shaft from chloride corrosion should use X111-T5-K4 flux core as weld metal

The study of loss of the tensile stress of the steel bar by rust corrosion was proceeded by select the sample steel bars which be corroded to analyze the physical character and find the percentage of weight decrease. Then made the comparison with the steel bar – weight of Thai Industrial Standard 20-2543 (RB) and 24-2536 (DB) and tested the resistance of tensile force. The result found that the steel bar that had percentage of weight decrease at 1-2% would had percentage of tensile stress decreased at 9-15% and had percentage of stretch at 9-39%. When they were compared with the Thai Industrial Standard 20-2543 (RB) and 24-2536 (DB). Overall if the percentage of the weight of the steel bar was decreased at 1-2% the steel bar would can be used in building with unimportant structure such as ground slab by rub the rust off and had the sampling random for the strictly standard test