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Impact of pouring temperature on the mechanical properties of Al5.9Cu1.9Mg alloy

Akhyar Akhyar, Iswanto P.T., Malau V.

Archives of Materials Science and Engineering

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2022

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Vol. 113, nr 2

49--55

EN

Purpose: This experiment aims to determine the influence of pouring temperature on the hardness, impact energy, tensile strength, and changes in the microstructure of the Al-5.9Cu- 1.9Mg alloy. Design/methodology/approach: A total of three samples of aluminium alloy were heated to 688, 738, and 788°C, and poured into permanent moulds in form of plates at a constant temperature of 220°C. The cast products are machined according to testing standards for hardness, impact tests, and tensile strength. Findings: The results showed that the metal hardness and impact energy increased to 103 BHN and 7.48 J at 788°C, respectively, while the tensile strength rises as the temperatures decreases. Furthermore, the changes in the microstructure were affected, which indicated that all the properties of the aluminium alloy were influenced by the variations in temperature. Research limitations/implications: During the metal casting process, only three different pouring temperatures affected the properties of the metal alloy, therefore, there is a need for more variations. Practical implications: The proposed pouring temperature parameter is an important condition for industrial foundry applications to obtain the right product for use in a machining element. Originality/value: This research shows the influence of the difference in pouring temperatures on the properties of metal alloys due to casting, where they will be adapted for a particular use.

2

Effect of shot peening on microstructure, hardness, and corrosion resistance of AISI 316L

Iswanto P. T., Akhyar H., Faqihudin A.

Journal of Achievements in Materials and Manufacturing Engineering

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2018

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Vol. 89, nr 1

19--26

EN

Purpose: This research conducted to analyse the effect of shot peening on surface structure, hardness, and resistance to corrosion of AISI 316L. Design/methodology/approach: The shot peening process is carried out on the surface of 316L stainless steel samples with four peening durations, and they are 2, 4, 15, and 30 minutes. Shot ball steel with diameter 0.4 mm for metal shot blasting and model S110 of ISO 11124/3 and SAEJ827, with the chemical composition, are C (0.8-1.2 wt.%), Mn (0.6-1.2 wt.%), Si (min. 0.4 wt.%), S (max. 0.05 wt.%), P (max. 0.05 wt.%), with a hardness of steelball, about 40-50 HRC. The pressure of compressor kept constant at 8 bar with a diameter of the nozzle is 5 mm, and the distance between the nozzle and the sample surface variated by 6 cm and 12 cm for each shooting duration. Findings: The result shows that the shot peening increases the surface hardness of the material, changes the microstructure on the surface layer and increases the resistance to corrosion. Shot peening with 30 minutes of shooting duration and 6 cm of shooting distance can improve the metal surface properties, which has a surface hardness of 772.23 HV and good on corrosion resistance. Research limitations/implications: The results of this experiment show that shot peening distance of 6 cm for 30 minutes achieved the highest surface hardness of AISI 316L. The corrosion rate decline with increasing duration and nearer distance of shooting balls. Practical implications: In the development of the implant material, AISI 316L need to be improved, its material properties, so it can be used safely and compatibly. Shot peening is a cold working process of metal to increase the material properties by shooting the steel ball into the surface of a material. Originality/value: Based on the experimental results it was obtained that variations shot peening distance and shot peening duration can change grain morphologies, subsequently affect hardness and corrosion resistance on AISI 316L.

3

Modification of Constrained Rod Casting Mold for New Hot Tearing Measurement

Malau V., Akhyar H., Iswanto P. T.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 3

1201--1208

EN

Hot tearing severity was evaluated in this experiment by introducing a new apparatus called Constrained Rod Casting Modified Horizontal (CRCM-Horizontal). Six constraint bars with different lengths can produce hot tearing on the cast sample. Mold position was modified from vertical to horizontal and the shape was changed from a harp shape to a star shape, which allows for the liquid metal to feed into each rod cavity simultaneously. Hot tearing development was recorded along the bars by a digital camera. A new Hot Tearing Susceptibility ( HTS) formula was developed for quantitative investigation of hot tearing on a cast sample. The parameters of the HTS formula are bar length of cast sample (Li), tear severity (Ci) and location of hot tear (Pi). Footprint charts and hot tear scales are used to illustrate hot tearing severity. The experiment was conducted with Al-1.36Zn-1.19Si and Al-5.9Cu-1.9Mg alloys to investigate the sensibility of the apparatus and modification its operation.