scholarly journals CALCULATION ON THE STRENGTH OF DEFORMING ELEMENTS AND DEVELOPMENT OF FIRMWARE STRUCTURES FOR ULTRASOUND PROCESSING

2021 ◽  
pp. 135-144
Author(s):  
Volodymyr Rutkevych ◽  
Vitaliy Kushnir
Keyword(s):  
Tensile Strength ◽  
Residual Stresses ◽  
Thermal Stresses ◽  
Ultrasonic Vibrations ◽  
Acoustic Parameters ◽  
Considerable Decrease ◽  
A Value ◽  
Acoustic Contact ◽  
Force Characteristics ◽  
Metal And Alloys

The possibility of increasing the efficiency and expanding the technological capabilities of the process of deforming drawing, by studying the contact phenomena and force characteristics of the process of deforming drawing (flashing) with the imposition of ultrasonic vibrations on the tool. The main advantages of deforming drawing with application of ultrasound are noted, among which it is necessary to allocate considerable decrease in force parameters of process, reduction of level of residual stresses, increase of accuracy of the processed details. Also, the application of ultrasound allows you to process parts made of metal and alloys, the processing of which in normal conditions is impossible and requires special techniques. It is noted that it is not possible to use known designs of broaches and firmware when flashing with the application of ultrasonic vibrations, because the firmware must have all the dimensions related to the acoustic parameters and the deforming element must be placed on the mandrel with tension to create good acoustic contact between the mandrel and the element. Prefabricated deforming firmware for processing holes with the imposition of longitudinal ultrasonic vibrations has been developed and a method for calculating their deforming elements for strength has been proposed. The performed calculations showed that the calculated stresses differ from the allowable ones by no more than 15-20 %. From the above calculations it is seen that the deforming element can be destroyed, both under the action of the working load in the process of flashing, and under the action of thermal stresses after the exit of the element from the machined hole. This difference in the results of research can be explained by the fact that the order of tensile strength is a value that has a large scattering zone and in different studies it is different. The results of research on the strength of deforming elements can be used in engineering calculations in the design of prefabricated tools for drawing holes with ultrasound.

Residual stresses in metal rolled with application of ultrasonic vibrations

1971 ◽  
Vol 13 (1) ◽  
pp. 74-75
Author(s):  
V. P. Severdenko ◽  
A. V. Stepanenko ◽  
I. V. Zayash ◽  
P. S. Ovchinnik�v
Keyword(s):  
Residual Stresses ◽  
Ultrasonic Vibrations

scholarly journals An Elastoplastic Thermal-Stress Analysis of a Free Plate

1956 ◽  
Vol 23 (3) ◽  
pp. 395-402
Author(s):  
Jerome Weiner
Keyword(s):  
Thermal Stress ◽  
Residual Stresses ◽  
Stress Analysis ◽  
Uniqueness Theorem ◽  
Unique Solution ◽  
Heat Input ◽  
Thermal Stresses ◽  
Elastoplastic Material ◽  
Heuristic Solution ◽  
Peak Magnitude

Abstract The thermal stresses in a free plate of elastoplastic material subjected to a varying heat input over one face are determined. A heuristic solution is first found by suitable modifications of the known elastic solution. It is then verified that the solution satisfies all the conditions of the appropriate uniqueness theorem and represents therefore the unique solution to the problem. Residual stresses are determined and found to depend markedly on the peak magnitude of the heat input.

Residual Stress Analysis in Different Thickness TiN Coatings on High-Speed-Steel Substrates

2011 ◽  
Vol 239-242 ◽  
pp. 2331-2335 ◽  
Author(s):  
Fang Mei ◽  
Guang Zhou Sui ◽  
Man Feng Gong
Keyword(s):  
Residual Stresses ◽  
High Speed ◽  
Thermal Stresses ◽  
High Speed Steel ◽  
X Ray Diffraction ◽  
Tin Coatings ◽  
Compressive Stresses ◽  
M2 High Speed Steel ◽  
Steel Substrates ◽  
Different Thickness

TiN coatings were deposited on AISI M2 high-speed-steel (HSS) substrates by multi-arc ion plating technique. The thickness of substrate was 1.0 mm and five thicknesses of TiN coatings were 3.0, 5.0, 7.0, 9.0 and 11.0 μm, respectively. X-ray diffraction (XRD) has been used for measuring residual stresses. The stresses along five different directions (Ψ=0°, 20.7°, 30°, 37.8° and 45°) have been measured by recording the peak positions of TiN (220) reflection for each 2θ at different tilt angles Ψ. Residual compressive stresses present in the TiN coatings. Furthermore, the results revealed that the value of the residual stresses in TiN coatings was high. While the coatings thickness changed from 3 to 11 μm, the residual stresses varied from -3.22 to -2.04 GPa, the intrinsic stresses -1.32 to -0.14 GPa, the thermal stresses -1.86 to -1.75 GPa. The residual stresses in TiN coatings showed a nonlinear change. When the coatings thickness was about 8 μm, the residual stresses in TiN coatings reached to the maximum value.

Effect of Compliance on Residual Stresses in Manufacturing with Moving Heat Sources

2021 ◽  
pp. 1-53
Author(s):  
Mitchell R. Grams ◽  
Patricio F. Mendez
Keyword(s):  
Residual Stresses ◽  
Thermal Stresses ◽  
Ad Hoc ◽  
Mathematical Treatment ◽  
Heat Sources ◽  
Plastic Part ◽  
Practical Applications ◽  
Tendon Force ◽  
Design Calculations ◽  
Force Concept

Abstract Manufacturing processes involving moving heat sources include additive manufacturing, welding, laser processing (cladding and heat treatment), machining, and grinding. These processes involve high local thermal stresses that induce plasticity and result in permanent residual stress and distortion. The residual stresses are typically calculated numerically at great computational expense despite the fact that the inelastic fraction of the domain is very small. Efforts to decouple the small plastic part from the large elastic part have led to the development of the tendon force concept. The tendon force can be predicted analytically for the case of infinitely rigid components; however, this limitation has prevented the broader use of the concept in practical applications. This work presents a rigorous mathematical treatment using dimensional analysis, asymptotics, and blending which demonstrates that the effect of geometric compliance depends on a single dimensionless group, the Okerblom number. Closed-form expressions are derived to predict the effect of compliance without the need for empirical ad-hoc fitting or calibration. The proposed expressions require input of only material properties and tabulated process parameters, and are thus ideally suited for use in metamodels and design calculations, as well as incorporation into engineering codes and standards.

Pengolahan Bioplastik Dari Campuran Gliserol, CMC Dan Karagenan

2021 ◽  
Vol 10 (3) ◽  
pp. 321-326
Author(s):  
Muhammad Abdul Zaky ◽  
Rini Pramesti ◽  
Ali Ridlo
Keyword(s):  
Tensile Strength ◽  
Film Thickness ◽  
Kappaphycus Alvarezii ◽  
Environmentally Friendly ◽  
Extraction Process ◽  
Alkaline Treatment ◽  
Plastic Packaging ◽  
A Value ◽  
Best Value ◽  
Experimental Laboratory

Indonesia menghasilkan 64 juta ton sampah di laut dan 3,2 juta ton di antaranya adalah plastik. Pencemaran tersebut mendorong pencarian plastik berbahan dasar ramah lingkungan yang dapat terurai . Bioplastik yang merupakan alternatif kemasan plastik dan bersifat ramah lingkungan. Berbagai bahan dasar pembuatan bioplastik telah ditemukan, salah satunya dasar karagenan. Penelitian ini bertujuan mengetahui karakteristik bioplastik hasil ekstraksi karagenan rumput laut Kappaphycus alvarezii dan mengetahui konsentrasi terbaik bioplastik hasil ekstraksi karagenan berdasarkan tebal film, kuat tarik dan persen pemanjangan. Metode yang digunakan adalah eksperimental laboratoris. Ekstraksi menggunakan perlakuan alkali dengan larutan KOH. Proses ekstraksi menghasilkan tepung karagenan yang digunakan sebagai bahan pembuatan bioplastik. Pembuatan bioplastik menggunakan campuran karagenan dengan 5 variasi massa karagenan, gliserol 10 ml dan 1,2 g CMC. Hasil ekstraksi menghasilkan rendemen 41,12%, kadar air 2,75%, kadar abu 19,10%, kekuatan gel 452,38 dyne/cm2dan viskositas 8,33 cP. Hasil penelitian tentang nilai ketebalan film bioplastik terbaik pada karagenan 3,5 g yaitu 0,093 mm, kuat tarik terbaik pada 1,5 g yaitu 2,587 Mpa, elongasi terbaik pada karagenan 1,5 g sebesar 44,992%. Berdasarkan data tersebut, hasil penelitian ini dapat diaplikasikan sebagai kemasan primer produk pangan. Sea pollution in Indonesia has increased every year with one of the pollutants is plastic. Indonesia produces 64 million tons of waste at sea and 3.2 million tons of which are plastic. The pollution is encouraging researchers to create plastic-based materials that are environmentally friendly and biodegradable. Bioplastics are an environmentally friendly alternative to plastic packaging. This study aims to determine the characteristics of bioplastics extracted from Kappaphycus alvarezii seaweed carrageenan and determine the best concentration of bioplastics from the extraction based on film thickness, tensile strength, and elongation percentage. The method that used in the research is experimental laboratory. The extraction uses alkaline treatment with KOH solution. The extraction process produces carrageenan flour which will be used as a bioplastic material. Making bioplastics using a mixture of carrageenan with 5 variations of concentration, glycerol 10 ml and 1.2 g CMC. The results of extraction showing 41.12% yield, 2.75% moisture content, 19.10% ash content, 452.38 dyne / cm2 gel strength, 8.33 cP viscosity. Carrageenan with the best value of bioplastic film thickness is 3.5 g which is 0.093 mm, the best tensile strength is achieved at 1.5 g with a tensile strength value of 2.587 MPa, the best elongation is achieved at 1.5 g with a value of 44.992%. Based on data showing that this research can be applied as primary packaging for food products.

Effect of Interfacial Nanostructure on Mode Mixity in Directly Bonded Carbon Fiber Reinforced Thermoplastic Laminates and Aluminum Alloy With Thermal Stresses

2020 ◽  
Author(s):  
Hiroki Ota ◽  
Kristine Munk Jespersen ◽  
Kei Saito ◽  
Keita Wada ◽  
Kazuki Okamoto ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Aluminum Alloy ◽  
Carbon Fiber ◽  
Residual Stresses ◽  
Adhesive Bonding ◽  
Thermal Stresses ◽  
Fiber Reinforced ◽  
Mode Mixity ◽  
Mechanical Joining ◽  
Carbon Fiber Reinforced

Abstract In recent years, for the aim of weight reduction of transportation equipment, carbon fiber reinforced thermoplastics (CFRTPs), which have high recyclability and formability, are becoming suitable for mass production. Additionally, with the development of multi-material structures, excellent technologies for joining metal and CFRTPs are required. In present industry, joining between dissimilar materials include adhesive bonding and mechanical joining methods, however, these methods still have some problems, and therefore an alternative bonding method without adhesive and mechanical joining is required for joining CFRTPs and metals. Thus, this study focused on direct bonding between CFRTP and an aluminum alloy, by producing a nanostructure on the surface of the aluminum alloy. The nanostructure penetrates the CFRTP matrix causing an anchoring effect, which results in significant bonding strength improvement. The influence of the nanostructure on the fracture toughness for the directly bonded CFRTP and aluminum was evaluated by static double cantilever beam (DCB) testing. Due to the difference of the thermal expansion coefficients between the CFRTP laminates and the aluminum alloy, significant residual stresses are generated. The effect of the thermal residual stresses on the fracture toughness along with the resulting mode mixity (mode I and II) was calculated. It is found that the thermal stresses introduce a significant mode mixity of the fracture toughness.

scholarly journals The Utilization of Waste Cooking Oil (WCO) as A Mixture of Polyol Sourcein. The Production of Polyurethane Using Toluene Diisocyanate

2019 ◽  
Vol 35 (1) ◽  
pp. 221-227
Author(s):  
Maulida Lubis ◽  
Mara Bangun Harahap ◽  
Iriany Iriany ◽  
Muhammad Hendra S. Ginting ◽  
Iqbal Navissyah Lazuardi ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Impact Strength ◽  
Waste Cooking Oil ◽  
Raw Material ◽  
Toluene Diisocyanate ◽  
Elongation At Break ◽  
Cooking Oil ◽  
A Value ◽  
Stirring Time

Cooking oil waste that has been disposed could contamine the environment. However, if it is processed well, it can potentially become a raw material of polyurethane. The aim of this study was to determine the best polyurethane on the tensile strength, impact strength, elongation at break, water absorption, characterization of Fourier Transform Infra-Red (FTIR) and the characterization of Scanning Electron Microscopy (SEM). The variables used in this study were ambient process temperature with 440 rpm stirring speed, 1-minute stirring time, the ratio of polyoland WCO was 7:3 (% w/w), and the ratio of Toluene Diisocyanate (TDI) and WCO was 1:1; 1:2; 1:3; 1:4 (% w/w). The results obtained from the analysis of the best tensile strength against the polyurethane synthetic was in the 1:1 ratio of mixed variations between oil and TDI with a value of 0.403 MPa. The best impact strength was in the ratio of mixed variations between oil and TDI with 1:4 (% w/w) with a value of 600.975 J/m2. The best elongation at break against polyurethane foam synthetic was in the 1:3 ratio of mixture variations of oil and TDI with a value of 4.506%.

Invsetigation about Residual Stresses of Plasma-Spraying Sm2Zr2O7/YSZ Thermal Barrier Coatings of Different Substrate Conditions

2011 ◽  
Vol 308-310 ◽  
pp. 1177-1181 ◽  
Author(s):  
Hong Song Zhang ◽  
Gang Yi Cai ◽  
Shu Sen Yang
Keyword(s):  
Residual Stress ◽  
Residual Stresses ◽  
Plasma Spraying ◽  
Thermal Stresses ◽  
Thermal Barrier ◽  
Shear Stresses ◽  
Substrate Thickness ◽  
Optimum Thickness ◽  
Slight Effect ◽  
Axial Residual Stress

Effect of substrate conditions, including material type, thickness and radius of substrate, on residual thermal stresses of plasma spraying Sm2Zr2O7/YSZ TBCs was analyzed through finite element method in this paper. The radial and shear stresses of the coating decrease with increasing of distance from the center to edge, and they decrease abruptly at the edge of the specimen, while the axial residal stress increase abruptly at the edge of substrate. All residual stresses increase with increasing of thermal expansion coefficient of substrate. The thickness of substrate has slight effect on the radial residual stress, axial residual stress and shear stress are almost uneffected by substrate thickness. The optimum thickness of substrate is 10mm. Radius of substrate have no effect on radial stress when it is greater than 28mm.

Development of Residual Stress Improvement for Nuclear Pressure Vessel Instrumentation Nozzle Weld Joint (P-43+P-8) by Means of Induction Heating

2006 ◽  
Author(s):  
Takuro Terajima ◽  
Takashi Hirano
Keyword(s):  
Mechanical Properties ◽  
Residual Stress ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Residual Stresses ◽  
Induction Heating ◽  
Weld Joint ◽  
Thermal Stresses ◽  
Pressure Vessels ◽  
Weld Joints

As a counter measurement of intergranular stress corrosion cracking (IGSCC) in boiling water reactors, the induction heating stress improvement (IHSI) has been developed as a method to improve the stress factor, especially residual stresses in affected areas of pipe joint welds. In this method, a pipe is heated from the outside by an induction coil and cooled from the inside with water simultaneously. By thermal stresses to produce a temperature differential between the inner and outer pipe surfaces, the residual stress inside the pipe is improved compression. IHSI had been applied to weld joints of austenitic stainless steel pipes (P-8+P-8). However IHSI had not been applied to weld joints of nickel-chromium-iron alloy (P-43) and austenitic stainless steel (P-8). This weld joint (P-43+P-8) is used for instrumentation nozzles in nuclear power plants’ reactor pressure vessels. Therefore for the purpose of applying IHSI to this one, we studied the following. i) Investigation of IHSI conditions (Essential Variables); ii) Residual stresses after IHSI; iii) Mechanical properties after IHSI. This paper explains that IHSI is sufficiently effective in improvement of the residual stresses for this weld joint (P-43+P-8), and that IHSI does not cause negative effects by results of mechanical properties, and IHSI is verified concerning applying it to this kind of weld joint.

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