Case Study Development of Welding Machine for Sterling Silver Jewelry Parts With 500-amp electrical arc system for welding closing porous jewelry after casting. The problem can be solved by welding closing porous or by the jewelry. It is an alternative to repairing the work piece. The efficiency of electrical arc welding equipment can be repaired to a certain extent. Based on the results of the experiments the welding and repairing porous porcelain parts were rated at 500 amperes by random sampling of 4 time slots 5 seconds 10 seconds 15 seconds and 20 seconds. Examine the most appropriate porous or porous workpiece for 20 seconds with 18 complete workpieces capable of sealing or milling. A good percentage of 90 percent of the performance of an electrical arc welding machine for welding sealing or cutting.

This Research is to Study the Development of 6k White Gold Low Alloys Metal for Jewelry Production The Optimum Conditions for Casting Jewelry and Jewelry were Investigated. The Results of the Experiments Show that the Chemical Composition of the 8k White Gold Low Alloys is Slightly Different when Compared with XRF (X-ray Fluorescence Spectrometers) Pre-and Post-Melting Quantities The Heat of the Test Specimen was found to be 33.33%Au+50.67%Ag+10%Cu+5%Zn+1%Sn33.33%Au+50.67% Ag+8% Cu+7%Zn+1%Sn and 33.33%Au+50.67%Ag+8%Cu+8%Zn+0%Sn It is Found that the Heat from the Beginning to the Level of Change before the Liquid is used the Average Temperature of 458.9 – 326.3 Degrees Celsius Respectively 33.33%Au+50.67%Ag+8%Cu+7%Zn+1%Sn It is the Formula that Gives the Lowest Value of Liquid State Change from 326.3 Degrees Celsius to the Best Value of this Experiment. Suitable for use in the Manufacture of Jewelry due to its Melting Ability for Molding. Melting for Molding and Formed by Hand. The Amount of Zinc(Zn) may be an Important Factor in the Variation which is Directly Proportional to the Maximum Increase in the Final order of 7 Percent

This Research is a Development of 8k White Gold low Alloy Metal Components for Jewelry Pieces. By Study and Analyze the Influence of Silver Alloy Gold Alloy Bronze Alloy Zinc Alloy and Tin Alloy. Which Affect Microstructure and Mechanical Properties. (The Different of Color Scales) And Resistance Behavior of Lowered 8k White Gold Alloy in Varies Ratio. The Results Showed that Tests and Analysis to Find the Quantities of Elements has found out that Chemical Components of 8k White Gold Low Alloy Metal had a Little Different Quantities when Compared Between Before and After Centrifugal Casting Process. The Tests and Analysis Results of Mechanical Properties of Test Pieces Showed that the Hardness and Tensile Strength of 8k White Gold Low Alloy Metal with Mixture of 33.33%Au+50.67%Ag+10%Cu+5%Zn+1%Sn had Minimum Ultimate Tensile Strength Equal 0.54 kN/mm2 Minimum Elongation Percentage of 55% and Maximum Hardness of 137.0 HV. The Test Results also Show that the Mechanical Properties of the Material are Brittle Material. When Perform a Forming Process the Pieces will be Easily Broken which was Meant that the Forming Process would be Difficult. But The Color Level of the Test Pieces at this Composite Ratio had the Best Metal Color Level. The Brightness L * = 74.87 was a * = -0.89 b * = 13.74 and the Value of ΔE with the Lowest Color Difference Level of 1.35. Compared to other Varies Ratio. It Showed that 8k White Gold Low Alloy Metal Test Pieces were Very Green and Came out Slightly Yellow Compared to the Blue Line that Approached the Standard Line. These Properties were the Physical Properties Required in 8k White Gold Low Alloy Metal Jewelry Pieces Production. Also there were the Results of 8k White Gold Low Alloy Metal in Two Formulas 8k 33.33%Au+50.67%Ag +8%Cu+7%Zn+1%Sn 33.33%Au+50.67%Ag+8%Cu+8%Zn+0%Sn. These Formulas had Tensile Strength in the Range of 1.10 0.60 kN /mm2 Elongation Percentage in the Range of 70 61% and Hardness of 115.6 123.3HV Respectively. The Results of the Mechanical Properties Test of the Test Pieces Showed that 8k White Gold Low Alloy Metal 33.33% Au+50.67%Ag+8%Cu+7%Zn+1%Sn has Similar Tensile Strength but Maximum Elongation Percentage of 70% and Minimum Hardness of 115.6HV. Which was Suitable for Forming Because of good Ductility and Stretchness Properties (Ductile Material). Forming would be Easy. These were Good Mechanical Properties for Forming Precious Metals.

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.

Nowadays one of the automotive engineering is conductivity of brake pads playing a role in friction coefficient which means safety of customer. Thus thermal properties have been improved using composited materials. This project aims to study the heat capacity behavior of 3 different brake pads which are supported by the company Compact International (1994) Ltd. For experimental works temperature based on brake condition was simulated from 05 to 003°C at 5 MPa of pressure. By standard JIS D4413 testing condition of pressure was referred. The heat capacity values of brake pads are calculated under the temperature conditions. As a result of testing brake pad made of copper or high metal powders result in relatively low heat capacity. On the other hand brake pads containing fiber and a large amount of fillers result in an increased heat capacity and stability in various temperature conditions. The heat capacity varied according to the operating temperature. In addition the lubricant contained in the brake pads affects the higher heat capacity and stability at various temperatures.