개량 Al-6.5Si 합금의 미세조직, 인장 및 충격 인성에 미치는 합금 원소 첨가의 영향 = Effect of Alloying Element Addition on the Microstructure, Tensile and Impact Toughness of the Modified Al-6.5Si Alloy

다국어 초록 (Multilingual Abstract)

Low-cost alloying elements were added to a modified Al-6.5Si alloy and its microstructure, tensile and impact toughness properties were investigated. The alloying elements added were Mg, Zn, and Cu, and two kinds of alloy A (Mg:0.5, Zn:1, Cu:1.5 wt.%) and alloy B (Mg:2, Zn:1.5, Cu:2 wt.%) were prepared. In the as-cast Al-6.5Si alloys, Si phases were distributed at the dendrite interfaces, and Al2Cu, Mg2Si, Al6 (Fe,Mn) and Al5 (Fe,Mn)Si precipitates were also observed. The size and fraction of casting defects were measured to be higher for alloy A than for alloy B. The secondary dendrite arm spacing of alloy B was finer than that of alloy A. It was confirmed by the JMatPro S/W that the cooling rate of alloy B could be more rapid than alloy A. The alloy B had higher hardness and strength compared to the values of alloy A. However, the alloy A showed better impact toughness than alloy B. Based on the above results, the deformation mechanism of Al-6.5Si alloy and the improving method for mechanical properties were also discussed.

참고문헌 (Reference)

1 박경섭, "아공정 Al-Si 합금에서 Si 함량과 냉각속도에 따른 제이차수지상간격의 변화" 한국주조공학회 37 (37): 108-114, 2017

2 성효경, "베이나이트계 고강도강의 합금원소와 냉각조건이 미세조직, 인장성질, 충격성질에 미치는 영향" 대한금속·재료학회 48 (48): 798-806, 2010

3 O. Lashkari, "X-ray microtomographic characterization of porosity in aluminum alloy A356" 40 : 991-999, 2009

4 H. R. Lashgari, "The effect of strontium on the microstructure, porosity and tensile properties of A356-10%B4C cast composite" 517 : 170-179, 2009

5 J. Pavlovic-Krstic, "The effect of mould temperature and cooling conditions on the size of secondary dendrite armspacing in Al-7Si-3Cu alloy" 15 (15): 105-113, 2009

6 M. B. Djurdjevič, "The effect of major alloying elements on the size of the secondary dendrite arm spacing in the as-cast Al-Si-Cu alloys" 12 (12): 19-24, 2012

7 J. Hirsch, "Superior light metals by texture engineering : Optimized aluminum and magnesium alloys for automotive applications" 61 (61): 818-843, 2013

8 Q.-Z. Dong, "Prediction of mechanical properties of Al alloys with change of cooling rate" 9 (9): 381-386, 2012

9 S. W. Choi, "Precipitation dependence of thermal properties for Al–Si–Mg–Cu–(Ti) alloy with various heat treatment" 647 : 1091-1097, 2015

10 Z. Li, "Parameters controlling the performance of AA319-type alloys: Part I. Tensile properties" 367 : 96-110, 2004

11 E. Ogris, "On the silicon spheroidization in Al-Si alloys" 2 (2): 263-269, 2002

12 T. Wang, "Modeling of microporosity formation during solidification of aluminum alloys" 84 : 012046-, 2015

13 V. C. Srivastava, "Microstructural modifications induced during spray deposition of Al–Si–Fe alloys and their mechanical properties" 471 (471): 38-49, 2007

14 김영균, "Mg+A2Ca 첨가 ADC12 (Al-Si-Cu) 합금의 미세조직, 인장 및 고주기 피로 특성" 한국소성가공학회 26 (26): 306-313, 2017

15 M. F. Ibrahim, "Metallurgical parameters controlling the microstructure and hardness of Al–Si–Cu–Mg base alloys" 32 (32): 2130-2142, 2011

16 S. G. Shabestari, "Influence of modification, solidification conditions and heat treatment on the microstructure and mechanical properties of A356 aluminum alloy" 39 : 2023-2032, 2004

17 Y. J. Li, "Influence of Cu on the mechanical properties and precipitation behavior AlSi7Mg0.5 alloy during aging treatment" 54 (54): 99-103, 2006

18 A. Tajiri, "Fatigue limit prediction of large scale cast aluminum alloy A356" 3 : 924-929, 2014

19 A. K. Dahle, "Eutectic modification and microstructure development in Al–Si alloys" 413~414 : 243-248, 2005

20 O. Engler, "Effect of natural ageing and pre-straining on strength and anisotropy in aluminium alloy AA 6016" 639 : 65-74, 2015

21 I. Aguilera-Luna, "Effect of cooling rate and Mg content on the Al–Si eutectic for Al–Si–Cu–Mg alloys" 95 : 211-218, 2014

22 Z. Li, "Effect of alloying elements on the segregation and dissolution of CuAl2 phase in Al–Si–Cu 319 alloys" 38 : 1203-1218, 2003

23 S. Derin, "Effect of Strontium Addition on Microstructure and Mechanical Properties of AlSi7Mg0.3 Alloy" 11 (11): 688-695, 2016

24 함기수, "Effect of Heat Treatment on Tensile and Fatigue Deformation Behavior of Extruded Al-12 wt%Si Alloy" 대한금속·재료학회 23 (23): 35-42, 2017

25 J. Z. Yi, "Effect of Fe-content of fatigue crack initiation and propagation in a cast aluminum-silicon alloy (A356-T6)" 386 (386): 396-407, 2004

26 F. Grosselle, "Correlation between microstructure and mechanical properties of Al-Si cast alloys" 101 (101): 25-32, 2009

27 M. Dehnavi, "Cooling Curve Analysis in Binary Al-Cu Alloys:Part I-Effect of Cooling Rate and Copper Content on the Eutectic Formation" 21 (21): 195-205, 2015

28 L. Lu, "Combining Sr and Na addition in hypoeutectic Al–Si foundry alloys" 399 (399): 244-253, 2005

29 H. Beumler, "Analysis of modified 319 aluminum alloy" 96 : 1-12, 1988

30 P. Jimbert, "Analysis and comparative study of factors affecting quality in the hemming of 6016T4AA performed by means of electromagnetic forming and process characterization" 211 (211): 916-924, 2011

31 J. R. Davis, "Alloying: Understanding the Basics" ASM International 351-416, 2001

32 조재섭, "Al-Zn-Mg계 알루미늄 합금의 유동성에 미치는 합금원소의 영향" 한국주조공학회 32 (32): 127-132, 2012