scholarly journals Stiffener Design to Maintain Line Heating Efficiency during the Lifting Process Considering Phase Transformation

Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 119
Author(s):  
Hong-Jun Noh ◽  
Hun-Bong Lim ◽  
Hee-Chan Yoon ◽  
Young-Hwan Han ◽  
Hyun-Ik Yang
Keyword(s):  
Phase Transformation ◽  
Physical Properties ◽  
Plate Theory ◽  
Superposition Principle ◽  
Steel Structures ◽  
Local Model ◽  
Line Heating ◽  
Shipbuilding Industry ◽  
Heating Efficiency ◽  
Main Technique

In the shipbuilding industry, welding is the main technique used to join steel structures. There is a lifting process, post-welding, that can eliminate the correction effect of line heating. Line heating is reperformed after the lifting process. This can significantly delay the ship assembly process. Herein, we present a design method for installing a permanent stiffener to avoid the disappearance of the line heating effect during the lifting process. The change in physical properties due to heating and cooling of the line heating is calculated. The limiting stress, at which the effect of the line heating completely disappears, based on the inherent strain theory, is obtained. The phase fraction by the cooling rate is calculated using the continuous cooling transformation diagram and the Kiustinen–Marburgerm equation. Physical properties affected by the phase transformation are calculated, considering the physical properties and fraction of each phase. The square plate theory and superposition principle are used to construct a local model, with a stiffener, of the ship block. The stress caused by the shape of the stiffener and the distance between the stiffeners were calculated for the local model. The calculated stress and the limiting stress were compared to determine, for the expected line heating efficiency, the most acceptable stiffener design. Finally, to confirm the elimination of the problem, the designed stiffener is analyzed using the finite element method.

DOMEX 550MC

Alloy Digest ◽  
2009 ◽  
Vol 58 (3) ◽  
Keyword(s):  
Physical Properties ◽  
Hsla Steel ◽  
Steel Structures ◽  
High Strength ◽  
Heat Treating ◽  
Bend Strength ◽  
Cold Forming ◽  
Wide Range ◽  
Hot Rolled ◽  
Earthmoving Machines

Abstract Domex 550MC is a hot-rolled, high-strength low-alloy (HSLA) steel for cold forming operations. It is available in thicknesses of 2.00-12.80 mm. The alloy meets or exceeds the requirements of S550MC in EN 10149-2. Applications include a wide range of fabricated components and steel structures, including truck chassis, crane booms, and earthmoving machines. This datasheet provides information on composition, physical properties, tensile properties, and bend strength as well as fatigue. It also includes information on forming, heat treating, and joining. Filing Code: SA-594. Producer or source: SSAB Swedish Steel Inc.

scholarly journals Phase Transformation and Physical Properties of Al N-Co Film

2013 ◽  
Vol 25 (10) ◽  
pp. 5879-5880
Author(s):  
C.S. Oh ◽  
S.C. Kil ◽  
C.S. Han
Keyword(s):  
Phase Transformation ◽  
Physical Properties

Fatigue Behaviour of Friction Stir Welded Steel Joints

2014 ◽  
Vol 891-892 ◽  
pp. 1488-1493 ◽  
Author(s):  
José Azevedo ◽  
Virgínia Infante ◽  
Luisa Quintino ◽  
Jorge dos Santos
Keyword(s):  
Base Material ◽  
Welding Process ◽  
Steel Structures ◽  
Fatigue Behaviour ◽  
Fatigue Tests ◽  
Fatigue Properties ◽  
Welded Steel ◽  
Shipbuilding Industry ◽  
Friction Stir ◽  
Steel Joints

The development and application of friction stir welding (FSW) technology in steel structures in the shipbuilding industry provide an effective tool of achieving superior joint integrity especially where reliability and damage tolerance are of major concerns. Since the shipbuilding components are inevitably subjected to dynamic or cyclic stresses in services, the fatigue properties of the friction stir welded joints must be properly evaluated to ensure the safety and longevity. This research intends to fulfill a clear knowledge gap that exists nowadays and, as such, it is dedicated to the study of welded steel shipbuilding joints in GL-A36 steel, with 4 mm thick. The fatigue resistance of base material and four plates in as-welded condition (using several different parameters, tools and pre-welding conditions) were investigated. The joints culminate globally with defect-free welds, from which tensile, microhardness, and fatigue analyses were performed. The fatigue tests were carried out with a constant amplitude loading, a stress ratio of R=0.1 and frequency between 100 and 120 Hz. The experimental results show the quality of the welding process applied to steel GL-A36 which is reflected in the mechanical properties of joints tested.

Effect of MnO2 Impurity on the PZT-PMN System Ceramics for Piezoelectric Transformer

2008 ◽  
Vol 55-57 ◽  
pp. 189-192
Author(s):  
Y. Suwan ◽  
Anuson Niyompan ◽  
Rungnapa Tipakontitikul ◽  
Pitak Laoratanakul
Keyword(s):  
Dielectric Constant ◽  
Grain Size ◽  
Phase Transformation ◽  
Physical Properties ◽  
Temperature Dependence ◽  
Room Temperature ◽  
Piezoelectric Properties ◽  
Relative Dielectric Constant ◽  
Linear Shrinkage ◽  
Poling Process

The PZT-PMN ceramics system was derived from Pb(Zr0.5Ti0.5)O3 and Pb(Mg2/3Nb1/3)O3 based compositions those obtained via the columbite method. The effect of MnO2 addition on microstructure, physical properties and piezoelectric properties were investigated. In this study, the composition with PZT/PMN ratio of 1:1 was selected. To observe the effect of MnO2 adding, its concentration was varied in range 0-10 mol%. Green pellets were sintered at temperature 1250oC for 4 hours. For piezoelectric investigation, the ceramics pellets were subjected to a poling process. The XRD results show that there is no phase transformation observed for all sintered PZT-PMN samples with presence of MnO2. The SEM micrographs reveal that MnO2 can enhance sinterability as evidenced by lowering of porosity and increasing of grain size with increasing of MnO2 content. Increasing of linear shrinkage and apparent densities also confirmed such effect. Improvement of d33 from 28 to 114 pC/N could only found for MnO2 in range 0 to 4 mol%. For higher MnO2 content, there is only slightly increased. However, increasing of kp with increasing of MnO2 is clearly observed. While dielectric constant measured at room temperature and at frequency 1 kHz is higher for ceramics without MnO2 doping and it decreases with increasing MnO2 concentration. The temperature dependence of relative dielectric constant go to peak of value about 6000 at temperature around 180oC and shifting of these peaks with frequency can only be observed for samples with higher MnO2 content. This indicates a normal ferroelectric behavior for sample with lower MnO2 and there are converted to relaxor after MnO2 increased.

DOMEX 500MC

Alloy Digest ◽  
2009 ◽  
Vol 58 (2) ◽  
Keyword(s):  
Fracture Toughness ◽  
Physical Properties ◽  
Hsla Steel ◽  
Steel Structures ◽  
High Strength ◽  
Heat Treating ◽  
Bend Strength ◽  
Cold Forming ◽  
Wide Range ◽  
Hot Rolled

Abstract Domex 500MC is a hot-rolled, high-strength low-alloy (HSLA) steel for cold forming operations. It is available in thicknesses of 2.00-13.00 mm. The alloy meets or exceeds the requirements of S500MC in EN 10149-2. Applications include a wide range of fabricated components and steel structures, including truck chassis and crane booms. This datasheet provides information on composition, physical properties, tensile properties, and bend strength as well as fracture toughness. It also includes information on forming, heat treating, and joining. Filing Code: SA-592. Producer or source: SSAB Swedish Steel Inc.

Analysis of Plate Examples by Difference Methods and the Superposition Principle

1936 ◽  
Vol 3 (3) ◽  
pp. A81-A90
Author(s):  
D. L. Holl
Keyword(s):  
Boundary Conditions ◽  
Critical Stress ◽  
Plate Theory ◽  
Superposition Principle ◽  
Equivalent Stress ◽  
Lower Surface ◽  
The Other ◽  
Principle Of Superposition ◽  
Various Boundary Conditions ◽  
Actual Plate

Abstract In this paper the author applies the membrane analogs of H. Marcus to some elementary cases of thin homogeneous isotropic square plates having central-point loads and various boundary conditions. The analogy is made possible by two theorems: (a) The deflection of a membrane loaded with loads proportional to those on a given plate may be considered as the sum of the principal moments of the actual plate. (b) A second membrane may be loaded with elastic weights proportional to these moment sums and, subject to appropriate boundary conditions, the deflections of the latter membrane will be proportional to the deflections of the actual plate under the given loading system. The principle of superposition of deflection surfaces or equivalent stress systems is utilized in this paper both by difference and differential methods. The problems treated are (1) a square plate with pinned or simply supported edges, (2) two opposite edges pinned and the other two free, (3) two opposite edges pinned and the other two clamped, (4) all four edges clamped, (5) all four edges free with only corner post supports. The correct critical stress at the center of the lower surface of the plate was obtained from special thick-plate theory for a particular thickness-to-span ratio. The effect of this critical stress on the whole plate action is depicted for various boundary conditions.

ÇELİK DİRSEK ÜRETİMİNİN SONLU ELEMANLAR ANALİZİ YÖNTEMİ İLE MODELLENMESİ VE ÜRETİM PARAMETRELERİNİN OPTİMİZASYONU

2021 ◽  
Vol 8 (16) ◽  
pp. 49-67
Author(s):  
Mustafa Ay ◽  
Selim Hartomacıoğlu ◽  
Mühendisi Murat Manav ◽  
Şaban Saraç
Keyword(s):  
Production Process ◽  
Water Distribution ◽  
Manufacturing Industry ◽  
Steel Structures ◽  
Cost Effective ◽  
Production Costs ◽  
Production Environment ◽  
Element Analysis ◽  
Shipbuilding Industry ◽  
Cold Forming

With the advancement of today's technologies, parts of pipe and elbow elements, natural gas pipelines, petrochemicals, machinery manufacturing industry, water distribution and flow systems, sewage systems, foundation piles, shipbuilding industry, nurse containers, aviation, space and defense industry, pipe networks, refineries , steel structures, tube and pipe engineering, etc. widely used in areas. In this study, extrusion method, which is one of the cold forming methods of elbow pipes, has been investigated. When the literature is examined, the production conditions of steel pipes and the problems that occur in production have been examined by different people and suggestions have been made. In this study, the production process of AISI 316L (EN 1.4404) quality stainless steel elbow pipes has been investigated. The mold design model created with the Solidworks program was transferred to the non-linear finite element analysis software ANSYS program for simulations. The process was modeled and simulated in the transient structural analysis section of the ANSYS program. In the process of transforming the pipe into an elbow product, we have learned about the stress distributions and obtaining the total deformation changes on the elbow. The parameters of the production process have been optimized by comparing the work done in the simulation and experimental data. In this way, cost-effective production is aimed by minimizing production costs. The data was extracted by simulating the production environment and conditions.

Study of Thermo-Physical Properties of Selected Nickel-Based Superalloys With Use of DTA Method

2012 ◽  
Author(s):  
Jana Dobrovska ◽  
Simona Zla ◽  
Frantisek Kavicka ◽  
Bedrich Smetana ◽  
Vlastimil Vodarek
Keyword(s):  
Phase Transformation ◽  
Physical Properties ◽  
Phase Transformations ◽  
Solidus Temperature ◽  
Experimental System ◽  
Reaction Scheme ◽  
Transformation Temperatures ◽  
Heating And Cooling ◽  
Temperature Heating ◽  
Thermo Physical Properties

The presented paper deals with study of thermo-physical properties of cast complex alloyed nickel based superalloys IN713LC, IN738LC and IN792-5A. In this work the technique of Differential Thermal Analysis was selected for acquisition and comparison of the phase transformation temperatures. The samples taken from superalloys in as received state were analysed at heating and cooling rates of 1, 5, 10, and 20 K/min using the experimental system Setaram SETSYS 18TM. Moreover, the transformation temperatures for zero heating/cooling rate were calculated. Based on a comparison of these temperatures it is possible to make the following conclusions: (i) The alloy IN792-5A has the highest temperature of solubility of the strengthening phase γ′ (1235°C); (ii) the highest liquidus temperature (heating) obtained by extrapolation was found in the alloy IN713LC (1349°C), the lowest solidus temperature (heating) was found for the alloy IN738LC (1212°C); (iii) At cooling an undercooling occurred in all alloys. In general it may be stated that the biggest under-cooling (TS, 47°C) was recorded in the alloy IN792 5A; (iv) The width of the interval of the heat treatment window was the biggest in alloy IN713LC (44°C); (v) The alloy IN738LC is characterised by the widest interval of melting (124°C) and solidification (134°C), while the alloy IN792 5A has the narrowest interval of melting (82°C) and at the same time almost the same interval of solidification as the alloy IN738LC (129°C); (vi) The obtained phase transformation temperatures were compared with the values of phase transformations temperatures calculated on the basis of established relationships. In order to obtain more precise description of the behaviour of Ni-based superalloys, during controlled heating/cooling of the initial material (as received state) during DTA analyses, all the samples of superalloys were subjected to a phase analysis using scanning electron microscopy. The course of phase transformations, in all the studied superalloys (IN713LC, IN738LC, IN792 5A) is likely to run according to the following reaction scheme (L = melt): L ↔ γ, L ↔ γ + MC, L ↔ γ/γ′, L ↔ γ + minority phases (such as M3B2, phase η), γ ↔ γ′.

scholarly journals Investigation on the physical properties and diffusion layer phase transformation at the interface of Sialon-Duplex Stainless-Steel bonding

2021 ◽  
Vol 15 (3) ◽  
pp. 8450-8458
Author(s):  
Mohamed Ahmed Rady ◽  
Patthi Hussain ◽  
Nagoor Basha Shaik ◽  
Balaji Bakthavatchalam
Keyword(s):  
Stainless Steel ◽  
Phase Transformation ◽  
Physical Properties ◽  
Duplex Stainless Steel ◽  
Diffusion Layer ◽  
Diffusion Bonding ◽  
Research Work ◽  
Hot Press ◽  
Press Bonding ◽  
And Diffusion

Joining SiALON to duplex stainless steel utilizes the properties of two materials which may provide an opportunity for distinctive applications. Ceramic is hard and operates at a high temperature but it is brittle whereas metal is tough but it can work at a low temperature. The benefits of the best properties of both materials can be utilized by joining them. The objectives of the research work are to investigate the physical properties and the phase transformation at the interface and at the inter-diffusion layer in between the SiAlON and duplex stainless steel. The experiment incorporated nitriding, then diffusion bonding the duplex stainless steel using the hot press. Bonding was carried out at 1200°C for the holding times of 30 minutes and 1 hour.  Metallography and micro analyses were conducted to achieve the above objectives. The study has demonstrated that 30 minutes joining time is sufficient to develop the thickness of the interface. However, 1 hour joining duration achieved cohesive and sound diffusion bonding of the SiAlON to duplex stainless steel. This is possible due to the formation of diffusion interlayer which accommodates the residual stress presence during cooling down process.

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