The Effect of Motorcycle Wheels (Original Equipment Manufacturer) Reconditioning Process on Mechanical Properties and Microstructure

Wheels are an essential component of a vehicle. Material damage or failure on casting wheel-type wheels is primarily because these wheels receive a reasonably hard impact load due to uneven road conditions or potholes. This condition makes the wheels unable to function normally, and components must be replaced. Given the relatively high cost of replacing wheels, several options are offered to vehicle owners (consumers) to have their wheels reconditioned. This study aims to analyze the effect of the reconditioning process on the mechanical properties and microstructure of the casting wheel material. The sample material is taken from the Original Equipment Manufacturer (OEM) wheel casting wheel in the Disk section for impact testing, Rim for hardness, and microstructure tests. The results are that the reconditioning process affects the mechanical properties and microstructure of the original equipment manufacturer (OEM) alloy wheel material. The decrease in hardness value was 68.86 HBW to 61.59 HBW from the conditions before and after reconditioning. The impact test results where the impact energy absorption is greater after reconditioning is 29.24 J, and the average impact value for wheel specimens after reconditioning is 0.2902 J/mm2. The impact energy value before reconditioning is 7.87 J, and the average impact value is 0.0973 J/mm2. The microstructure obtained is hypereutectic, and the reconditioning process has little effect on the dendritic structure

APLIKASI BIOMATERIAL DALAM KARDIOLOGI: STENT KORONARIA

Research in the field of materials has become widespread. Biomaterials is a term that is aimed at material that is part of medical implants. Biomaterials have been used by humans both to improve appearance and restore organ function. Modern biomaterials are still needed and biofunctionality study of biocompatibility of implants. Biocompatibility must be referring to the material properties to be safe and work in harmony with the body without causing other harmful effects. An important aspect to consider from the biocompatibility of products starting from the fabrication process, corrosion resistance and modification of implant materials and coatings

Penetap tulang besi-keluli tahan karat terbiodegradasi menggunakan kaedah kimpalan geseran

For the treatments of bone fracture, surgery will be conducted by installing the implant to maintain the proper position of fractured bone until the bone has completely joined. The implant removal surgery have been discussed till now due to the complication cases, the reaction of rejection from patient body and the risks of refracture. This research introduced a new system for bone-fracture screw application whereby it can minimise the procedure of bone fracture surgery and it enable to avoid the occurrence of bone refracture. The screw was made from two different materials which are SS316L (inert metal) and pure iron (biodegradable metal). In this system, the SS316L part will be removed while the pure iron will be remained in the bone. The combination of these two different metals was performed using friction welding technique. The welding joint of SS316L and pure Fe was successfully produced and then the screw product was also fabricated. The result from cell viability test of Normal Human Osteoblasts (NHOst) cells have shown that all the welded zones were biocompatible and have not induced any toxicity towards the cells. The concentration of the iron ion from the immersion corrosion test was 0.002375 mg/ml and this value is still below the safe concentration level of 0.050 mg/ml. The strength to pull out the screw from the cow bone tested ex vivo was 3879 ± 248 N while the pull-out failure only occurred on the cow bone (not on the screw). Further researches could be performed in future in order to know the effect of Fe ion distribution towards the organs of animal model through histology assessment

Corrosion monitoring of friction welded joints results between low carbon steel-SS 202

Pada penelitian ini, pemantauan korosi dilakukan pada sambungan las gesekan baja karbon rendah dan baja tahan karat austenitik (SS 202) yang disimulasikan dalam larutan biologis. Penelitian ini bertujuan menghitung laju korosi sambungan las gesek baja karbon rendah dan SS 202 serta mengevaluasi kekasaran permukaan yang terjadi pada zona pengelasan. Dari hasil sambungan las, dibuat sampel uji korosi dengan mewakili zona pengelasan. Sebelum perendaman, permukaan sampel dibersihkan dan dipoles sebelum perendaman menggunakan larutan elektrolit NaCl 0,9wt.%. Percobaan dijalankan pada 2, 4, 6, dan 8 minggu masing-masing sampel. Hasil penelitian menunjukkan bahwa laju korosi sambungan las gesek baja karbon rendah dan SS 202 tertinggi sebesar 0,0167 mm/tahun, dan terendah 0,0127 mm/tahun. Pada saat yang sama, area sambungan las yang memiliki kekasaran permukaan tertinggi terjadi pada zona plastis. Disimpulkan bahwa seluruh zona pengelasan menunjukkan potensi korosi yang seragam kecuali zona plastis yang menunjukkan perilaku korosi galvanik.   ABSTRACT In this study, corrosion monitoring was carried out in the friction welded joint of low carbon steel and austenitic stainless steel (SS 202) simulated in a biological solution. This study aims to calculate the corrosion rate of friction welding joints of low carbon steel and SS 202 and evaluate the surface roughness that occurs in the welding zone. From the results of welded joints, corrosion test samples were made by representing the welding zone. Prior to immersion, the surface of the sample was cleaned and polished before immersion using a 0.9wt.% NaCl electrolyte solution. Experiments were run at 2, 4, 6, and 8 weeks of each sample. The results showed that the corrosion rate of friction welding joints for low carbon steel and SS 202, the highest was 0.0167 mm/year, and the lowest was 0.0127 mm/year. At the same time, the welded joint area that has the highest surface roughness occurs in the plasticized zone. It was concluded that the entire welding zone showed uniform corrosion potential except for the plasticized zone, which showed galvanic corrosion behavior

ANALISIS POTENSI LIMBAH TULANG AYAM DAN IKAN DARI PKL SEBAGAI SUMBER MINERAL KALSIUM FOSFAT

This study aimed to find out how much potential waste from chicken bones and fish collected from street vendors in the city of Pekanbaru to pulverized bone and mineral calcium phosphate nanoparticle size. This research is motivated by many vendors who are considered disturbing the aesthetics and cleanliness of the city. The research was conducted in the city of Pekanbaru by using primary data obtained from a survey of street vendors. While secondary data obtained from the Office of Market town of Pekanbaru, statistical data and the results of previous studies. Data samples are taken randomly from street vendors in the city of Pekanbaru based on the types of food sold as roasted chicken and fried catfish. The process of making bone powder are derived from chicken and fishbones through several stages. For bone drying process is done at a temperature of 100 OC for 15 minutes. As for the bone turnover process is performed at a temperature of 700 OC for 6 hours. The results showed that the huge potential of the waste bones if used as a source of mineral raw materials Calcium Phosphate. This research could also describe an increase in economic value if it produces powder bone and bone powder with the size of the nanoparticles

Innovation for Making Portable Induction Furniture as a Solution for System Waste Handling Post-vaccination COVID-19 Vaccine

The world was shocked by the outbreak of a new virus called Coronavirus Disease 2019 (COVID-19) in 2020. The use of personal protective equipment in the community during a pandemic resulted in an increase in the amount of medical waste. Syringe is one of the medical waste from the COVID-19 pandemic which is classified as metal waste. One of the solutions offered is a medical waste incinerator. By studying the medical waste incinerator model in hospitals, the researchers finally took the initiative to design a simple incinerator. The incinerator to be used is a portable induction type. It is hoped that the use of this incinerator will be able to overcome the existing medical waste problem. Keywords: Evaluation, Incinerator, Garbage, Induction

STUDI PENYAMBUNGAN MATERIAL KATUP KENDARAAN MENJADI BIMETAL MENGGUNAKAN METODE Friction Welding

Katup merupakan suatu komponen pengatur proses membuka-menutup pada saluran masuk dan buang sebuah motor bakar. Selama ini, komponen katup kendaraan terbuat dari logam baja yang memiliki massa jenis yang lebih besar jika dibandingkan dengan material aluminium. Penelitian ini bertujuan untuk mengganti sebagian material katup dengan material aluminium dengan harapan dapat meringankan kinerja putaran mesin kendaraan. Proses penyambungan dilakukan dengan metode friction welding yang menjadi tren metode penyambungan untuk material yang berbeda saat ini. Parameter pengelasan yang digunakan untuk friction welding seperti friction time, friction pressure, forging pressure dan burn off berdasarkan parameter penelitian terdahulu. Hasil sambungan las nantinya dilakukan pengujian mekanik mengikuti standar ASTM E8 dan ASTM E290. Distribusi kekerasan pada daerah lasan jugadilakukan evaluasi menggunakan standar ASTM E10-15a. Hasil percobaan akan menampilkan sifat mekanik sambungan las dan pengurangan massa jenis dari komponen katup yang dikembangkan

Mechanical and corrosion properties of partially degradable bone screws made of pure iron and stainless steel 316L by friction welding

This paper reports a series of in vitro, ex vivo and in vivo mechanical and corrosion studies of pin and screw prototype made of friction welded pure iron and 316L type stainless steel aiming to evaluate the applicability of the partially removable bone screws. Results showed that the pin possesses bending, tensile and torsional strengths of 1706±147, 666±7 and 0.34±0.03 MPa, respectively. The pin degraded at an average weight loss rate of 17.15×10−5 g cm−2 day−1 and released Fe ions at an average concentration of 2.38 ppm. Plastic deformation induced by torsion increased the corrosion rate of the pin from 0.0014 to 0.0137 mm year−1. The maximum pull-out load of the screw prototypes was 3800 N with a calculated failure strength by shear load equal to 22.2 kN which is higher than the strength of the cortical bone. Detailed analysis of the rat’s blood cells during 60 days of the pin implantation indicated a normal response with low neutrophils/ lymphocytes ratio of 0.3‒0.5. Iron ion concentration in the rat’s blood slightly increased from 55 to 61 ppm without affecting the tissue recovering and healing phase. Histological evaluation confirmed the presence of macrophage cells as a normal response to the released iron particles around the iron section of the pin

Experimental & Numerical study on COVID-19 Waste Treatment Using a Gasification Type Incinerator: Laboratory Scale

Due to the COVID-19 pandemic, the use of personal protective equipment in the community has contributed to the increasing amount of medical waste. Medical waste from the COVID-19 pandemic is classified as infectious medical waste which is waste related to patients who need isolation from infectious diseases. one of the solutions offered is a medical waste incinerator. By studying the medical waste incinerator model in the hospital, the researchers finally took the initiative to do a simple incinerator design. the incinerator to be used is updraft gasifier type. It is hoped that the use of this incinerator will be able to solve the existing medical waste problem. In this study, the researchers use experemental approach to get the basic data from the reactor. After gain the data, then the researcher use numerical approach which is using ansys softwere to get a better look of the temperature contour on the rector. From both study, researcher can conclude tha it would take an upgrade on the existing blower to incenerate the medical waste on a safely temperature