The present study features analytical and experimental results of optimizing resistance spot welding performed using a pneumatic force system (PFS). The optimization was performed to join SECC-AF (JIS G 3313) galvanized steel material with SPCC-SD low carbon steel. The SECC-AF is an SPCC-SD (JIS G 3141) sheet plate coated with zinc (Zn) with a thickness of about 2.5 microns. The zinc coating on the metal surface causes its weldability to decrease. This study aims to obtain the highest tensile-shear strength test results from the combination of the specified resistance spot welding parameters. The research method used the Taguchi method using four variables and a combination of experimental levels. The experimental levels are 2-levels for the first parameter and 3-levels for other parameters. The Taguchi optimization experimental results achieved the highest tensile-shear strength at 5049.64 N. It properly worked at 22 squeeze time cycles, 25 kA of welding current, and 0.6-second welding time and 12 holding-time cycles. The S/N ratio analysis found that the welding current had the most significant effect, followed by welding time, squeeze time, and holding time. The delta S/N ratio values were 1.05, 0.67, 0.57 and 0.29, respectively.
This research analyses v-bending results using galvanized SGCC (JIS G 3302) sheet steel. The accuracy of the angle and dimensions of the bending results are the significant elements of the bending process that must be achieved. The bending spring-back/spring-go phenomenon has an impact on bending angle accuracy. If proper parameters are chosen, the spring-tub/spring-go angle should be minimized. This study aimed to see how the proposed v-bending process affected the spring-tub/spring-go angle value. An experimental approach was selected in this study. V-die bending opening, V-die punch angle, V-die punch speed, and bending force are all input parameters for the v-bending process. Meanwhile, in this study, galvanized steel with a thickness of 1.2 mm was used. The results of the ANOVA evaluation showed that the v-die punch speed and bending force are two parameters that affect the response of the variable, with a percentage contribution of 31.0% each. The minimum spring-back angle was found in the second sample, while the minimum spring-go angle was found in the fourth sample
Crack failure often occurs in piping installations, especially in the welding area which can be caused by excessive stress or corrosion of the material. In this case, the crack failure in the HAZ area will be discussed near the pipe connected to the valve for the heat transfer fluid line. The method used in this paper is the inspection of the attached materials using OES (Optical emission spectroscope), observation of pipe and valve joints and failure analysis. From the results of material inspection, it was found that the pipe used was ASTM A106, then from the microstructure it was seen that the grain dimensions were not homogeneous, it would cause the strength of material heterogeneity, then from visual observation, it could be seen that pipe joints and valve misalignment occurred.
Sand casting merupakan salah satu metode pengecoran logam yang masih digunakan di industri hingga saat ini. Proses pengecoran dengan metode sand casting menggunakan dua jenis cetakan, yaitu cetakan pasir kering dan cetakan pasir basah. Pada proses pengecoran menggunakan cetakan pasir basah tidak semua produk hasil pengecoran dapat digunakan karena terdapat produk yang tidak memenuhi spesifikasi penggunaan produk, seperti kekasaran permukaan coran, intrusi logam cair ke dalam cetakan, gelembung udara, rongga, kegagalan cetakan, dan inklusi terak. Pembentukan cacat ini salah satunya dipengaruhi oleh permeabilitas atau campuran komposisi pasir dan bentonit yang kurang baik. Adapun peneliti melakukan pengamatan yaitu pengujian karakterisasi sifat fisik dan kimia bentonit Australia adalah difraksi sinar X, distribusi ukuran, swelling index, pH Value, methylene blue value dan kadar air. Nilai kadar senyawa Natrium Oksida (Na2O) yang diperoleh sebesar 4,7% dan Kalsium Oksida (CaO) sebesar 3,5%. Hal ini menunjukkan bahwa basis bentonit australia merupakan basis natrium, didukung oleh hasil pengujian swelling index, bentonit Australia mengalami mengembangkan hingga 15,5 kali lipat yaitu 33 ml/2gr dan nilai pH berada pada rentang 8,5-9,8. Distribusi ukuran bentonit Australia didapatkan nilai P80 sebesar 2,25 mm. Hasil pengujian Methylene Blue Value (MBV), dengan larutan H2SO4 diperoleh bentuk halo pada konsentrasi H2SO4 2% sebanyak 21 ml. Hasil ini menunjukkan bahwa bentonit Australia dapat digunakan sebagai pengikat yang baik pada cetakan pasir basah untuk pengecoran logam.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.