In the present study, various quenching media were added as cooling media for the quenching after pack carburizing treatment. The aim of this research is to get a suitable cooling medium for pack carburizing quenching treatment to increase the wear resistance of low carbon steel. Many cylindrical specimens for the adhesion wear tests were prepared from the used SS400 steel according to ASTM G99-04 specifications. Two heat treatment processes, namely pack carburizing and quenching were done. Firstly, the specimens are pack-carburized at a temperature of 875 °C, soaking time of 2 hours and quenched. The carburizing agent consists of Pinctada maxima shell powder (PMSP) and corn cob charcoal with a weight ratio of 30:70 %. Different cooling media (water, 10 % NaCl solution, 10 % cane molasses) in the pack carburizing quenching treatment are subjected to different kinds of tests. The hardness test was performed using Vickers micro hardness tester, the wear resistance was used in adhesive wear test, the carbon content was determined and microstructure examination was made using a scanning electron microscope (SEM-EDX). The result showed that all cooling media contributed to an increase in mechanical properties (surface hardness number, wear resistance), carbon content and microstructure change. The use of cooling media in the pack carburizing quenching process generally increases the surface hardness number of the specimen. The highest surface hardness number was 595 kg/mm2, respectively using 10 % cane molasses. The work shows that cane molasses can be used as a cooling medium for pack carburizing quenching of SS400 steel and contributed to the improvement of wear resistance

The purpose of this study is to investigate and study the mechanical properties of polyethylene strukrur micro hybrid composites reinforced by fibers sisal and jute sacks.Preparation of composites by hand lay-up method with a ratio of fiber volume fraction of sisal and jute sacks 30%: 0%, 20%: 10%, 15%: 15%, 10%: 20%, 0%: 30%. With unidirectional sisal fiber orientation and fiber length random burlap gunny sack fibers 2 cm. Specimen testing is performed with a standard bending test ASTM D790, and microstructure.Test results obtained from the average bending strength of composites with high fiber volume ratio fraksin 30%: 0% is 74.43 Mpa. While the lowest average for bending strength found in composites with fiber volume fraction of 0%: 30%, the bending strength of 32.21 MPa. Therefore we can conclude the increasing volume fraction of sisal fiber with unidirectional fiber orientation, the higher the bending strength of its appeal and reverse the growing volume of burlap fibers with random orientation of the fibers feeding the lower the bending strength and the strength.

Tujuan dari penelitian ini adalah untuk mengetahui pengaruh penggunaan arang tongkol jagung dan serbuk cangkang kerang mutiara sebagai media carburizer pada proses pack carburizing terhadap sifa (struktur mikro) dan mekanis (uji kekerasan) baja karbon rendah. Bahan yang digunakan dalam penelitian ini adalah baja karbon rendah yang berbentuk selinder. Proses pembuatan spesimen dilakukan dengan pemotongan menjadi beberapa bagian, pemotongan dilakukan untuk memudahkan di dalam meletakan spesimen di dalam kotak karburisasi,kemudian serbuk arang kayu dan serbuk cangkang ditimbang sesuai dengan komposisi yang diinginkan dengan pencampuran serbuk cangkang kerang mutiara 5, 10 , 20 dan 25 (% berat). Spesimen dilakukan perlakuan panas pada temperature 9100C, 9300C, 9500C dengan penahanan waktu selama 90, dan 150 menit. Kemudian dilakukan Uji kekerasan Vickers, pengujian foto struktur mikro dan uji komposisi. Dari penelitian ini dapat disimpulkan bahwa nilai kekerasan tertinggi rata-rata pada penambahan 20% serbuk cangkang di peroleh sebesar 262,47 kg/mm2 dan kekerasan material awal diperoleh sebesar 144,08 kg/mm2. Dari hasil pengamatan struktur mikro dan uji komposisi diketahui bahwa terjadi pengerasan permukaan karena difusi karbon kedalam baja karbon randah.

Musa acuminata stem is an agricultural waste that has good economic potential. For this reason, efforts are needed to increase the saba banana tree not only as waste, but also to increase its function into natural fiber raw materials for polyester matrix composite reinforcement. The purpose of this study was to determine the characteristics of Musa acuminata stem fibre (MASF) from North Lombok Regency, Indonesia Country as a reinforcement for polyester matrix composites. In this study, the fiber (specimen), taken from pseudo stem Musa acuminata, which consists of three layers: outer, middle and inner stem. The ratting process is done mechanically using a fiber extraction machine. To remove impurities in the fiber, alkaline treatment was carried out, by soaking for 24 hours in a 5 % NaOH solution. To determine the characteristics, a scanning electron microscopy (SEM) test was carried out for MASF morphology analysis, chemical compound content testing, heat resistance testing, and fiber tensile strength testing. The results showed that the MASF of the outer layer pseudo-stem has a strong character. Fiber morphology is different, between the outer, middle and inner layers pseudo-stems. The cellulose content (73.12 %) was higher than the fiber of Fimbristylis globulosa, hemp, jute, rice straw, wheat straw, seaweed, sorghum straw, coir, and alpha grass. Less resistant to heat degradation because mass loss occurs at a constant rate up to 245 °C. The highest MASF, in the outer pseudo-stem layer it is 40–50 cm from the base stem. Its characteristics are better than other natural fibers so that its potential can be further developed as a reinforcement for polymer matrix composites

In the present research preparation and characterization of polyester composite reinforced hybrid fiber Hibiscus tiliaceust bark fiber (HTBF) and palm fibers (PF). PF is obtained from palm plantation in Kekait village. HTBF has gained from the beach Krandangan, West Lombok, Indonesia. The fibers were treated with alkali by soaking it in 5% NaOH solution for 2 days Composites were made using the vacuum infusion method. The matrix used is polyester resin BTQN 157. The volume fractions between palm fibers (PF) and Hibiscus tiliaceust bark fiber (HTBF) are, 5% : 25%, 10% : 20%, 15% : 15%, and 20% : 10 %. Specimens for tensile testing using the ASTM D638-03 Type I standard and impact testing using the Izod method, specimens using the ASTM D256-03 standard, and further Observation of the specimen fracture was carried out using Canon EOS 700D Kit (EF S18-55 IS STM) camera. The results of this study indicate the addition of the volume fraction of palm fiber (PF), affects the tensile strength, modulus of elasticity, impact toughness and the extent of the fracture shape of the specimen. As the volume fraction of PF increases, the tensile strength, modulus of elasticity, fracture area increases, but the impact toughness of the specimen decreases. The specimen is suitable to be used as a leveler, mainly crushing and destroying paddy fields