This research is aimed at investigating the amount of chromium carbide (Cr23C6) in stainless steel AISI 304 by electrochemical technique testing in calculating the Pa values that corresponding to sensitization stage and the corrosion behavior. The results will carry on to developing the welding process. The specimens were produced with Shielded Metal Arc Welding method. Moreover it was bending at the angle 0 90 and 180 degree and the process finished on post-heat treatment with different cool down conditions are 800ºC annealed in air cooled 1100ºC annealed in water cooled and annealed 1100ºC in air cooled respectively. The results show that: first conditional is appeared the maximum amount of Pa value (Pa > 0.4) indicating that more precipitation of Cr23C6 in heat affected zone (HAZ) of specimen. The second conditional is not found the sensitization stage because when the specimens were annealed at high temperature the chromium carbide will break up and residual stress in HAZ will decrease. At last conditional is found the less amount of Pa value; the reason of using high temperature on annealing process will decrease chromium carbide but slowly air-induced cooling must pass the critical temperature then some Cr23C6 will appear at grain boundary and cause of high corrosion rate. Concerning to the corrosion behavior the second conditional present the lowest corrosion rate corresponding to the better-quality of passive film. Whereas the first conditional shown the highest corrosion rate and low quality of passive film. Thus 1100ºC annealed with water cooled is excellent condition for developing the welding process.

The objective of this research is to increase the tool life of trimming process by surface coating technology. The procedure of this research consists of two sections. In the first section the friction coefficient was investigated with the ball on disk technique by using a tribometer. Steel ball was produced from cold work tool steel grade SKD11 (JIS) hardened to 60±2 HRC. Two types of surface coating namely AlCrN and TiAlN were conducted by PVD technique. Disk material used in this experiment was made by stainless steel JIS; SUS 304 of 2 mm thickness. For the second section the wear tests of trimming die were performed by using flat punch and inclined punch 45 degrees without surface coating as well as the inclined punch 45 degrees coated with AlCrN and TiAlN (PVD). Workpiece material used for the wear test was stainless steel JIS; SUS 304 of 2 mm thickness. Additionally the finite element analysis was carried out for explanation the deformation of the workpiece during trimming operation. Although the friction coefficient of the surface coating was higher than non-coating it could be extended the tool life ostensibly. As the result of FEM the inclined punch 45 degrees could be generated the long sheared surface more than the flat punch. This is due to the internal stress of workpiece that did not connect from the punch to the die so the crack propagation would be delayed. The inclined punch 45 degrees coated TiAlN has a highly durable which can be used up to 5000 strokes.

This research aims to develop the cement board from vesicular basalt fragment which reinforced with steel wire mesh. The ratio of Portland cement type1: fine sand: vesicular basalt fragment: sodium silicate: tap water was equal to 1: 2: 4: 0.03: 0.55 by weight. The 5 sizes of steel wire mesh (steel wire no.25) were installed including: 3/8” 1/2” 5/8” 3/4” and 1”. The cement boards were produced by compression machine. The property tests of cement-bonded fiberboard followed the TIS. 878-1994 standard (cement bonded particle board: high density). From the results the 3/4 of steel wire mesh size was the most suitable size for reinforcing the cement board from vesicular basalt fragment. This developed cement boards was the construction materials which had the high bending strength good thermal insulation and moisture protection properties.

The objectives of this research are to develop the knock down house to create the knowledge to test the properties to construction the prototype and to transfer the technology of easy transport knock down house for sufferer. The load and resistance factor design (LRFD) method was used to design the structure. From the design and testing the easy transport knock down house for sufferer is the square shape building with gable roof. The building size 4.00 x 4.00 square meters and height 2.40 meters which has 16.00 square meters of usable area and 1.20 meters of gable roof height. This knock down house can separate the usable area into 2 parts include bedroom and toilet. The cost of material is 125000 Baht per unit or 7812.5 Baht per square meter. The 6 wheel truck can transport this knock down house. The safety factor (S.F.) of this knock down house equal to 1.86. Moreover the knowledge can register the copyright names “The drawing of easy transport knock down house for sufferer” and draft the research paper names “The easy transport knock down house for sufferer” that are the way to transfer technology to target group.

The purpose of this research is to find the relation between stress and strain called as the Flow Stress Curve for 0.4 mm thickness stainless steel (SS 304). Two main methods are used: the Uniaxial tensile test and the Hydraulic Bulge Test (HBT). The relation between stress and strain from both methods would then be compared and simulated into cubic-shaped models by using Finite Element method. Results show that sheet metal formation simulated by using the flow stress curve obtained from Hydraulic bulge test can have the height of up to 40 millimeters before the work piece starts to lacerate. On the other hand if the flow stress curve obtained from Uniaxial tensile test is used the work piece will only be able to form about 15 millimeters before lacerating. The preliminary summary for this research can be said that the analysis for Hydraulic bulge test gives better results than Uniaxial tensile test as it has similar conditions to the actual formation process.