scholarly journals Hardness Analysis of Stone Breaker Chisel Made of Medium Carbon Steel as a Result of Hardening Using Water Cooling Media

Teknomekanik ◽  
2020 ◽  
Vol 3 (1) ◽  
pp. 22-27
Author(s):  
Alan Novendra ◽  
Refdinal Refdinal ◽  
Sai Kham Le
Keyword(s):  
Hold Time ◽  
Good Condition ◽  
High Hardness ◽  
Medium Carbon Steel ◽  
Spring Steel ◽  
Leaf Spring ◽  
Water Cooling ◽  
Hardness Level ◽  
Cooling Media ◽  
The Right

Stone chisels produced by blacksmiths which are made using leaf spring steel are often too brittle or fragile so that when they are used, they often occur in the form of cracks and breaks. This study aims to determine the appropriate hardness level for stone chisels. The process is carried out by comparing the hardness level of stone chisels that have been used but still in good condition and those that have been damaged. Broken stone chisels have a high adequate hardness compared to good stone chisels so that damaged stone chisels can be reconditioned to get the right rock chisel hardness. Heat treatment is given to damaged stone chisels to improve the hardness level by normalizing the process to restore the initial mechanical properties of the steel and increasing the hardness of the chisel by heating the steel and then quenching it using water cooling media. Based on the experimental process carried out that the hardness level of a good stone chisel is between 228 HB to 320 HB by heating the duan spring steel to a temperature of 780ºC with a hold time of 10 minutes then cooling it quickly using water and stone chisels can break when it is used because it has a very high hardness.

scholarly journals Pengaruh Media Pendingin Terhadap Kekerasan Baja Tahan Karat Martensitik Type 431 Pada Proses Hardening dan Tempering

2018 ◽  
Vol 1 (02) ◽  
pp. 27-32
Author(s):  
Suyanta Suyanta ◽  
Subagiyo Subagiyo ◽  
Syamsul Hadi ◽  
Zahratul Jannah
Keyword(s):  
Stainless Steel ◽  
Stainless Steels ◽  
Air Conditioning ◽  
Cutting Tool ◽  
High Hardness ◽  
Air Cooling ◽  
Water Cooling ◽  
Cooling Medium ◽  
Hardening Process ◽  
Cooling Media

Stainless steels consist of several types such as Austenitic, Ferritic and Martensitic, Martensitic is one of the stainless steels that has a hardenability property, so it is suitable to be used as cutting tool components which require high hardness and corrosion resistance . The purpose of this study was to obtain information about the hardness of stainless steel martensitic type of hardening results with variations of cooling media. Methods of research used were experiments, ie hardening process by heating the material up to 1100oC temperature, held for 30 minutes, then cooled quickly on water, oil and the air, then heated back to 400oC temperature, cooled slowly, the results tested the hardness of Rockwell C method The results showed the type of stainless steel type martensitic 431 increased significantly after the Hardening process of 21.20 HRC before hardening, and after the hardening process to 47 , 6 HRC with water cooling, 47.9 HRC with oil cooling medium and 46.5 HRC for air cooling media, hardness after tempering down ranges from 6-7 HRC to 41.7 HRC for hardening with water cooling medium 41, 2HRC hardening results with oil cooling medium, and 40,4HRC un tuk hardening results with air conditioning medium.

scholarly journals PENGARUH QUENCHING DENGAN MEDIA PENDINGIN AIR DAN OLI TERHADAP MECHANICAL PROPERTIS BAJA S45C

JTAM ROTARY ◽  
2019 ◽  
Vol 1 (2) ◽  
pp. 183
Author(s):  
Deni Setiadi ◽  
Achmad Kusairi Samlawi
Keyword(s):  
Heat Treatment ◽  
High Hardness ◽  
Hardness Test ◽  
Water Cooling ◽  
Test Analysis ◽  
Cooling Medium ◽  
A Value ◽  
Before And After ◽  
Cooling Media

The role of steel in the industrial world today is very important, especially in terms of making components related to violence such as gears, fly wheel, axe, and so forth.This steel has a high hardness for components that require hardness, to uletan and resistance to friction. get hardness and resistance to steel hence need heat treatment process using Quenching process. The material of this research is S45C carbon steel with specimen number 1 for hardness test before treatment and after treatment with rockwell test, this process is done in Central Laboratory of FMIPA UM, unfortunate. In this process heat treatment is carried out at temperatures of 800⁰C and 900⁰C with water and oil cooling medium, from the results of comparative analysis on S45C steel before and after the treatment obtained increased hardness. This can be seen from the test analysis in which 93 kgf of hardness n is for the untreated specimens. At a temperature of 800⁰C with a water cooling medium at a crude value of 94.6 kgf, and on oil cooling medium at a hardness value of 92.5 kgf. At a temperature of 900⁰C with a water cooling medium at a hardness value of 93.5 kgf and on the oil cooling medium at a value of 93 kgf. Can be concluded from all the cooling media is the highest media water with value of violence 94.6 kgf.Keywords: S45C Steel, Quenching, Cooling

scholarly journals The Effect of Cooling Media on Tensile Strength of Medium Carbon Steel in Post Welding Process Using Electric Welding (SMAW) with E7018 Electrodes

Teknomekanik ◽  
2020 ◽  
Vol 3 (2) ◽  
pp. 62-69
Author(s):  
Herman Zulhafril ◽  
Jasman Jasman ◽  
Kimberly June Tespoer
Keyword(s):  
Tensile Strength ◽  
Carbon Steel ◽  
Room Temperature ◽  
Welding Process ◽  
Medium Carbon Steel ◽  
Air Cooling ◽  
Water Cooling ◽  
Medium Carbon ◽  
Electric Welding ◽  
Cooling Media

The use of cooling media in post welding process will affect the tensile strength of a material. This study aims to determine how much the influence of using cooling media in post welding and which cooling media is appropriate to use. The process is done by comparing the tensile strength of each cooling media, namely the cooling media of water, air, and coolant. The use of cooling media is carried out after the welding process, until the material that is ready to be welded reaches room temperature. Based on the experiments that have been conducted, the use of post-welding cooling media affects the tensile strength of medium carbon steel with the highest effect on the water cooling media, then the coolant media, and the lowest is the air cooling media. Therefore, the choice of the use of cooling media significantly affects the tensile strength of medium carbon steel in the post-welding process.

scholarly journals Analisis Pengaruh Media Pendingin Terhadap Kekerasan Baja S45C Pada Proses Hardening-Tempering

2021 ◽  
Vol 3 (1) ◽  
pp. 31-38
Author(s):  
Alfian Siswara Arlingga ◽  
Somawardi - ◽  
Sugianto -
Keyword(s):  
Heat Treatment ◽  
Mineral Water ◽  
Treatment Process ◽  
Salt Water ◽  
Coconut Water ◽  
Heat Treatment Process ◽  
Water Cooling ◽  
Table Salt ◽  
Hardness Level ◽  
Cooling Media

This study used an experimental method, in the form of the heat treatment hardening  930⁰C with the variations in the cooling media of the coconut water, table salt water, mineral waterwater, coolant radiator, and dromus water and variations in temperatures of tempering 200⁰C, 420⁰C, and 600⁰C, the specimens were cylindrical in diameter 25 mm and 20 mm in length, this study aims to determine the optimum hardness value of S45C steel specimens due to the heat treatment process hardening-tempering. From the results of the study, there is the effect of hardening 930⁰C there is the most optimal hardness value found in coconut water cooling media with the hardness level of 53.5 HRC. Under the influence of tempering 200⁰C there is the optimum hardness value found from the influence of mineral water cooling media with the hardness level of 50.7 HRC, while the influence of tempering 420⁰C there is the most optimal hardness value from the influence of mineral water cooling media with the hardness level of 41.8 HRC, and for tempering effect 600⁰C there is the most optimal hardness value available from the influence of the coconut water cooling media with the hardness level of 35.93 HRC.

CLINICAL CASE OF A MALIGNANT PECOMA OF THE LUNG

2019 ◽  
Vol 65 (5) ◽  
pp. 756-759
Author(s):  
Mikhail Postolov ◽  
Nadezhda Kovalenko ◽  
K. Babina ◽  
Stanislav Panin ◽  
Yelena Levchenko ◽  
...  
Keyword(s):  
Good Condition ◽  
Lung Neoplasm ◽  
Rare Condition ◽  
Epithelioid Cell ◽  
X Ray ◽  
Perivascular Epithelioid Cell ◽  
Mesenchymal Neoplasm ◽  
Preoperative Ct ◽  
Lymph Duct ◽  
The Right

Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal neoplasm characterized by expression of both mela-nocytic and smooth muscle markers. Only 10 primary malignant lung PEComas have been reported up to date. We report a 59-year-old male who presented with a lung neoplasm, found during the routine X-ray examination. Preoperative CT-scan revealed the 3,5-cm-sized mass, located at the border of the upper, middle and lower lobes of the right lung. Patient underwent a thoracotomy, resection of the upper, middle and lower lobes of the right lung accompanied with mediastinal lymphadenectomy. After surgery, chylothorax was revealed. Conservative treatment was unsuccessful, so we performed laparoscopic clipping of the thoracic lymph duct. Patient was dismissed from hospital on the 10-th day after the second operation in good condition. In this report, we intend to increase the limited knowledge relating to natural history and optimal treatment of such a rare condition as a primary malignant lung PEComa.

scholarly journals Spontaneous Resolution of Late-Onset, Symptomatic Fluid Collection Localized in the Meningioma Resection Cavity: A Case Report and Suggestion of Possible Pathogenesis

2021 ◽  
Vol 11 (3) ◽  
pp. 299
Author(s):  
Yeong Jin Kim ◽  
Tae-Young Jung ◽  
In-Young Kim ◽  
Shin Jung ◽  
Kyung-Sub Moon
Keyword(s):  
Brain Imaging ◽  
Late Onset ◽  
Fluid Collection ◽  
Good Condition ◽  
Treatment Strategies ◽  
Imaging Studies ◽  
Resection Cavity ◽  
Perilesional Edema ◽  
Posterior Neck ◽  
The Right

Postoperative complications after brain tumor surgery occur occasionally and it is important for clinicians to know how to properly manage each complication. Here, we described a rare case of late-onset, subdural fluid collection localized at the resection cavity that caused motor weakness after convexity meningioma resection, requiring differentiation from an abscess, to help clinicians determine treatment strategies. A 58-year-old right-handed female was admitted to the hospital with a headache and posterior neck pain. Brain computed tomography (CT) scans and magnetic resonance (MR) images showed a homogeneously enhanced, calcified, and multi-lobulated mass adjacent to the right motor strip without perilesional edema. The patient underwent surgery without incident or residual deficit and was discharged from the hospital in good condition. Six weeks after surgery, the patient complained of left arm monoparesis without infection-related symptoms. Brain imaging studies showed a localized fluid collection in the resection cavity with an enhanced margin and perilesional edema. Diffusion restriction was not detected. After three months of conservative treatment without surgery or antibiotics, she recovered from the neurologic deficits, and brain imaging studies showed the spontaneous regression of the fluid collection and perilesional edema. Late-onset, localized fluid collection at the resection cavity, which is similar to an abscess, could occur three to eight weeks after meningioma resection. When there are predisposing factors, including blood components and hemostatic materials in the surgical cavity, it is important for clinicians to understand this type of complication and choose conservative management as a feasible strategy.

Water-Jet Assisted Laser Surface Hardening of Medium Carbon Steel Using Fiber Laser

2018 ◽  
Author(s):  
Sagar Sarkar ◽  
Ashish Kumar Nath
Keyword(s):  
Surface Hardening ◽  
High Hardness ◽  
Medium Carbon Steel ◽  
Water Jet ◽  
Laser Surface ◽  
Peak Hardness ◽  
Bottom Surface ◽  
Thin Sheets ◽  
Laser Surface Hardening ◽  
Conventional Laser

Laser surface hardening of most of the industrial components require depth of surface modification in the range of 100–150 micron. Conventional laser surface hardening uses laser as a heat source to modify a particular area of the surface without melting in an inert gas environment. However, the hardened profile in this case shows peak hardness value at a certain depth from the top surface. Also, hardening the top surface to get relatively much higher hardness near the top surface in case of thin sheets becomes difficult due to accumulation of heat below the surface of the specimen which in turn lowers the cooling rate. Hence, self-quenching becomes inadequate. In the present study, an in-house fabricated laser processing head with coaxial water nozzle has been used to flow a laminar water-jet during the laser surface hardening process to induce forced convection at the top surface. Thus, heat gets carried away by the water-jet from the top surface and by the water from the bottom surface as well. Results show that with judicious selection of process parameters, it is possible to get higher hardness (800 HV) to that of conventional laser surface hardening (500 HV) at the top surface using this process. Present process can be used for those cases where high hardness values are required near the top surface specially for thin sheets and thermally sensitive materials.

scholarly journals Enhanced Axial Tension-tension Fatigue Resistance of a 51CrV4 Spring Steel by Cryogenic Treatment

2020 ◽  
Vol 72 (4) ◽  
pp. 138-151
Author(s):  
Chen Zhi ◽  
Gao Yuan ◽  
Yan Xian-Guo ◽  
Guo Hong ◽  
Huang Yao ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Cryogenic Treatment ◽  
Spring Steel ◽  
Thin Strip ◽  
Leaf Spring ◽  
Axial Tension ◽  
Axial Tensile ◽  
Tensile Fatigue ◽  
Conventional Heat Treatment ◽  
Dump Trucks

51CrV4 spring steel is widely used in heavy duty dump trucks ascribing to its superior mechanical properties. The fatigue life and strength of dump trucks are the main performance indicators that must be considered in the manufacturing process. Cryogenic treatment (CT) can improve the main performance of materials which has been proved by recently research. The effect of cryogenic treatment CT on the axial tensile fatigue strength of 51CrV4 spring steel was studied in this paper. The results showed that the axial tension-tension fatigue life of 51CrV4 spring steel after CT was significantly higher than conventional heat treatment (CHT) samples. The microstructure of 51CrV4 leaf spring material is mainly acicular bainite and thin strip martensite after CT. Compared with CHT, CT makes the microstructure of the material more compact. The introduction of cryogenic treatment (CT) before tempering makes the Ca element in the material aggregate, and the micro amount of Ca has the function of deoxidizing and desulphurizing and improving the morphology of sulfide, thus enhancing the fatigue life of the material.

Operations Research in Healthcare Supply Chain Management Under Fuzzy-Stochastic Environment

2020 ◽  
pp. 1833-1875
Author(s):  
S. Priyan ◽  
R Uthayakumar
Keyword(s):  
Customer Service ◽  
Operations Research ◽  
Health Care Systems ◽  
Good Condition ◽  
Vital Role ◽  
The People ◽  
Care Systems ◽  
Increase Productivity ◽  
The Right ◽  
Almost All

Operations research is for mankind in almost all aspects of our life. Applying the scientific method to the management of organizations, industry, government and other enterprises play a vital role in OR. It is used to increase productivity, to improve customer service, to improve quality and to reduce costs. Healthcare has attracted a great attention of governments in order to provide sufficient health services to the people. The provision of healthcare is very complicated and very responsible, that the right drug to the right people at the right time and in good condition to fight the disease. Today, the importance and significance of planning in healthcare can hardly be over emphasized when providing proper and adequate service continues to be a key concern of most countries. Operations research provides a wide range of methodologies that can help health care systems to significantly improve their operations. It helps to solve approximately all the problems involved in healthcare with its useful modeling techniques.

Effect of Microshot Peening on Surface Characteristics of Spring Steel

2010 ◽  
Vol 654-656 ◽  
pp. 374-377
Author(s):  
Yasunori Harada ◽  
Koji Yoshida
Keyword(s):  
Residual Stress ◽  
Shot Peening ◽  
Compressive Residual Stress ◽  
Cast Steel ◽  
High Hardness ◽  
Surface Characteristics ◽  
Spring Steel ◽  
Cemented Carbide ◽  
High Carbon ◽  
New Type

Shot peening is a surface treatment that improves the performance of engineering components. In conventional shot peening, the medium consists of small spheres, which are usually made of high-carbon cast steel; the diameter of the spheres is in the range from 0.3 to 1.2mm. More recently, however, a new type of microshot has been developed to enhance the peening effect. The diameter of the spheres in the new medium is in the range from 0.02 to 0.15mm. In the present study, the effect of microshot peening on the surface characteristics of spring steel was investigated. The injection method of the microshot was of the compressed air type. The microshots of 0.1mm diameter were high-carbon cast steel and cemented carbide, and the workpiece used was the commercially spring steel JIS-SUP10. The surface roughness, hardness and compressive residual stress of the peened workpieces were measured. The surface layer of the workpieces was sufficiently deformed by microshot peening. A high hardness or residual stress was observed near the surface. The use of hard microshots such as cemented carbide was found to cause a significantly enhanced peening effect for spring steel.

Sign in / Sign up

Export Citation Format

Share Document