• 제목/요약/키워드: Optimum welding condition

검색결과 142건 처리시간 0.033초

GA에 의한 차량용 이종재 최적점용접 조건 (Optimal Condition for Spot Weldment of Dissimilar Steel Sheet in Automotive)

  • 한재희;양성모;유효선;김태진
    • 한국자동차공학회논문집
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    • 제18권4호
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    • pp.68-73
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    • 2010
  • Welding conditions in process of spot welding must become optimum and need to guarantee stability and reliability of vehicle body considering dynamic load history. Because welding parameters in process of spot welding are various, it is difficult that the quality of spot weldment was included in the optimum levels. In this paper, we found the optimum welding conditions satisfying KS spot welding qualities using genetic algorithm and spot welding experiments of high tensile strength steel and galvanized steel. Those experiments were dissimilar weld and 2-lap spot welding. Genetic algorithm created random welding condition after that, selected optimum individuals by probability concept.

2024 알루미늄의 마찰용접에 관한 연구 (A study on friction welding of 2024 aluminium)

  • 송오성;강춘식
    • Journal of Welding and Joining
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    • 제8권3호
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    • pp.24-30
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    • 1990
  • 2024 Aluminium was welded by domestic manufactured continuous type friction welder. The problems and optimum condition were studied in 2024 Al-2024 Al cases. Mechanical tests and microstructure analysis were studeid. Interfacial temperature of welding was predicted by FDM. The obtained results are as follows: 1) In case of Al-Al, the optimum condition range was wide. 2) At the boundary zone, fine recrystallized zone was not harmful to the mechanical property and no growth of precipitation was observed. 3) In case of Al-Al, temperature gradient can be predictedby FDM and heat input can be taken as weld parameter.

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점용접 시 압흔 깊이 감소를 위한 최적 용접조건 선정에 관한 연구 (A Study on the Optimum Welding Conditions for Reducing the Depth of Indentation of Surface in Spot Welding)

  • 서승일;이재근;장상길;차병우
    • Journal of Welding and Joining
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    • 제14권2호
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    • pp.57-64
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    • 1996
  • In this paper, authors are trying to find optimum spot weldig conditions to minimize indentation of the plate surface which is crucial to quality of stainless rolling stocks. At first, to derive a simple equation to estimate the depth of indentation, a simplified one-dimensional bar model is proposed and validity of the model is confirmed by experiments. And also, to find proper welding conditions giving satisfied tensile strength of the welded joint, a simple formula is derived referring to the standard spot welding conditions by AWS. Optimization problem is formulated to find welding conditions such as welding current, time and applied force which give minimum indentation and proper tensile strength of joint, and solutions are found out. According to the results, the depth of indentation can be expressed by applied electrode froces and it can be shown that an optimum applied force exists.

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Effect of Process Parameters on the High Speed Seam Weldability of Tin Coated Steels for the Small Containers

  • Kim, K.C.;Lee, M.Y.
    • International Journal of Korean Welding Society
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    • 제1권1호
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    • pp.13-16
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    • 2001
  • High speed seam weldability of tin coated steels was investigated. Welding was performed by the laboratory wire seam welder that was equipped with process monitoring system Test results showed that increase in applied current and pressure reduced the total resistance across the welding electrodes. Lower and upper limits of welding current increased as the sheet thickness increased, while the acceptable welding condition range decreased. However, extremely low electrode pressure produced unstable welding condition range. The results also demonstrated that slower welding speeds widened the optimum welding heat input range.

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박판 강재의 고속 심 용접성에 미치는 Sn 도금의 영향 (Effect of Tin Coating on the High Speed Seam Weldability of Thn Gage Sheet Steels)

  • 김기철;이목영
    • Journal of Welding and Joining
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    • 제16권5호
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    • pp.86-92
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    • 1998
  • High speed wire seam weldability of tin coated thin gage sheet steels was investigated. Thickness and coating weight ranges of the test materials were 0.21~0.35mm and 1.1/1.1~2.8/11.2g/$m^2$, respectively. Test results indicated that the surface roughness value, Rz decreased as increasing the coating weight. The Rz was thought to be one of the important factors to influence the optimum welding condition range, $\triangle$Q. The $\triangle$Q showed close relationship with welding conditions such as welding pressure and travel speed. Higher welding pressure widened the $\triangle$Q while higher travel speed reduced the $\triangle$Q value. Results also demonstrated that tin coating weight should be optimized based on the weldability or the serviceability after welding. At th HAZ of sheet materials with thinner coating layer, tin depleted zone was produced since molten film of the coating material on the base metal agglomerated by the surface tension, which could result in reducing the corrosion resistance of the HAZ in the service environment.

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국산 SPS5 스프링강의 마찰용접에 관한 연구 (A Study on Friction Welding of Localized SPS5 Spring Steel)

  • 정순억
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집A
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    • pp.803-808
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    • 2000
  • This thesis studied whether friction welding of SPSS, localized torsion bar material could be accomplished or not. And then optimum welding conditions were examined and leaded through tensile, impact, torsion and hardness test after postweld heat treatment of the actual field condition. Obtained results were as follows; Linear relationship was existed between heating time and total upset, and a quadratic equation model could be made between tensile strength and heating time. Optimum welding conditions with fine structure were as follows in case total upset(U)=8.5mm; the number of rotations(n)=2,000 rpm, heating pressure($p_1$)=80MPa, upset pressure($p_2$)=200MPa, heating time($t_1$)=4sec, upset time($t_2$)=3 sec.

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알루미늄 5456-H116 합금에 대하여 최적 마찰교반 프로세싱 조건 규명 및 기계적 특성 평가 (Evaluation of Mechanical Characteristic and Investigation on Optimum Condition in Friction Stir Processing for 5456-H116 Al Alloy)

  • 박재철;김성종
    • 한국표면공학회지
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    • 제42권1호
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    • pp.13-20
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    • 2009
  • Friction stir welding(FSW) was developed as a new solid state welding technique by The Welding Institute (TWI). On the basis of FSW, a new processing technique, friction stir processing (FSP), has recently been developed. FSP has been applied to cast aluminum alloy to modify the microstructure to enhance mechanical characteristic. FSP is a new solid state processing technique for microstructural modification in metallic materials. FSP has been applied to aluminum alloy to modify the microstructure to enhance mechanical characteristic. In this study, we investigated optimum condition friction stir processing with the evaluation of mechanical characteristic for 5456-H116 Al alloy. The mechanical characteristics of base metal similar with in 15 mm/min, 250 RPM with full screw probe. This condition is concluded that optimum friction stir processing condition. The result of this investigation will be able to application for repair of welding part for aluminum ship.

하이드로포밍용 열연 강재의 레이저 용접성 및 성형 특성 (Laser Weldability and Formability of Hot Rolled Steels for Hydroforming Applications)

  • 이원범;이종봉
    • Journal of Welding and Joining
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    • 제22권6호
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    • pp.19-24
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    • 2004
  • The laser welding and its analysis of thin-sheet carbon steels were carried out with high power $CO_{2}$ laser. The main factor of weld quality of laser welding is gap and edge quality. This work was preformed to focus on the gap tolerance problem during laser welding. First, bead on plate welding of thin sheet was examined to investigate the effect of laser welding variables, and to obtain optimum welding condition. Butt welding was also carried out to show the effect of gap on the laser weldability of thin sheet. In order to investigate the effect of gap on formability of welded thin sheet, LDH test was caried out. At high welding speed, the partial penetration was obtained by low heat input. Otherwise, porosity was formed in the bead at low weld speed because of too much heat input. The optimum welding condition of welding was derived from bead width, penetration and hardness property. The maximum gap tolerance on laser welding was observed to be about 0.2mm. This gap size has good relationship with beam size of laser spot(about 0.3mm). The formability of welded sheet was about $80{\%}$ value of base metal and the gap size has not affected on the formability, although weld quality is dependent on the gap size.

압력용기용 1.25Cr-0.5Mo 강의 Submerged Arc Welding시 입열 및 PWHT 냉각속도가 용접부 기계적 성질에 미치는 영향 (Effect of Welding Heat Input and PWHT Cooling Rate on Mechanical Properties of Welded Region at SAW of 1.25Cr-0.5Mo Steel for Pressure Vessel)

  • 이동환;박종진
    • Journal of Welding and Joining
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    • 제22권5호
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    • pp.26-31
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    • 2004
  • In order to propose the optimum welding condition for field application, the effects of welding heat input and cooling rate at PWHT on the mechanical properties were investigated. Submerged arc welding of 1.25Cr-0.5Mo steel for pressure vessel was conducted at welding heat inputs of 15.2kJ/cm, 30.9kJ/cm, and 44.8kJ/cm, and cooling rates of 184$^{\circ}C$/hr, 55$^{\circ}C$/hr, and 2$0^{\circ}C$/hr at PWHT. From the test results, as the welding heat input increase up to 30.9kJ/cm, the changes of microstructure and impact toughness were small. At the heat input of 44.8kJ/cm, however, toughness decreased obviously due to the coarsening of coarse-grained HAZ and formation of ferrite at bainite grainboundary of weld metal. On the other hand, cooling rates at PWHT did not effect on the changes in microstructure and mechanical properties. Even though tensile strength and impact toughness at all welding conditions of this study were above the minimum specification requirement, it was confirmed that heat input of 30.9kJ/cm was the optimum welding condition to improve welding performance by higher heat input.

전기아연도금 강판의 점용접성에 미치는 용접조건과 압흔깊이에 관한 연구 (A Study on the Weldability & Indentation Depth Evaluation of Electrochemical Galvanized Steel Sheet according to the Welding Conditions)

  • 정영훈;허우진;백승세;권일현;양성모;유효선
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2003년도 추계학술발표대회 개요집
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    • pp.162-164
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    • 2003
  • Spot welding, a kind of electric resistance welding, has been used in many fields such as automobile, aircraft, and appliance industry. This paper is to investigate the relationship between tensile shear strength and indentation depth under various welding conditions. The tensile shear strength increases with increasing the welding current in the range of 6-l3kA. The optimum welding conditions were 200∼250kg welding force and 10∼15 cycles welding time at 9kA welding current for EZNCEN. The indentation depth for optimum welding condition was 0.6mm at 9kA welding curent and 200kg welding force, 0.17mm at 9kA welding current and 300kg welding force, 0.19mm at 9kA welding current and 10cycle, 0.17mm at 9kA welding current and 15cycle welding time, respectively.

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