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.

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This research is a Recearch and Development (R&D) by using ASSURE  model. The purpose of this research is 1) produce interactive multimedia, which are appropriate with the students’ need 2) to enhance students’ vocabulary of Arabic language. The data were collected by observation, interview, questionnaire, and document. The result of this research is 1) test of media expert showed the product is considered very good, the result is 4.60, 2) expert of the material showed that multimedia interactive is considered good, with result 3,97 3) the test of  one to one showed the  average  score  of 4,26 means the product is considered very good, the test of small group evaluation showed the avarage score of 4,38 is considered very good, and the test of field evaluation showed the average score of 4,42 means the product is very good, the conclusion is product can be appliying in learning.

The study of the MgH2 double-catalyzed Ni and SiC based storage system has been done. The objective of this study is to improve the hydrogen desorption temperature and the hydrogen desorption capacity. The material preparation was done through mechanical alloying technique. In this method, the milling of the material was carried out within 5 hours, 10 hours and 15 hours, with the ratio of the ball to the powder was and the speed of 350 rpm with the catalyst insertion catalyst by 5 wt% and 10 wt% SiC. Results from XRD measurements revealed that the sample was successfully reduced to a nanocrystal scale. The phase emerging from the XRD observation is the phase MgH2 as the main phase and followed by Ni and SiC phase as the minor phase. From the observation with SEM showing irregular particle shape, the particle size in the sample is not homogeneous because of the agglomeration effect and cold welding that causes the particle size to look large. The hydrogen release capacity was obtained in the samples which were milled for 10 hours at the weight of 5 wt% Ni-SiC catalyst with the release of 2.6 wt%. Based on observation with thermogravimetric analyzer (TGA), the lowest temperature was obtained in the samples which were milled 10 hours with catalyst 5 wt% SiC, which was 365 °C.

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