An Investigation on the Crystallographic and Morphologhyic Properties of the Austenite-Martensite Tranformation in Fe-31,5%Ni-10%Mn Alloy by X-Rays Methods

Year 2001, Issue: 002, 44 - 51, 15.06.2001

Hamza Yaşar Ocak İrfan Akgün

Abstract

In this study, Fe-31.5%Ni-10%Mn alloy prepared using special methods m TÜBİTAKMAM

was investigated. The crystallographic properties of austenite martensite phase

transformation created by different external physical effects have been studied with X-rays

Laue method. Austenite martensite phase transformaüon in alloy was observed as

isothermal and not changed by external physical effects. Experimental resaults showed that

the Lath martensit occured on surfaces of the samples. The lattice parameters of the

samples change depeding on the external physical effects and the martensite habit planes of

alloy were found as (225),, and (259)a considering to external physical effects.

Keywords

Austenite, Martensite, Lattice Prameter, Habit Planes, Isothermal

Fe-%31.5Ni-%10.Mn ALAŞIMINDA AUSTENİTE-MARTENSİTE FAZ DÖNÜŞÜMÜNÜN KRİSTALOGRAFİK VE YAPISAL ÖZELLİKLERİNİN X-IŞINLARI LAUE METODU İLE İNCELENMESİ

Abstract

Bu çalışmada özel metotlar kullanılarak TÜBİTAK-MAM ’da hazırlanan Fe-%31.5Ni-

%10Mn alaşımı incelendi Farklı dış fiziksel etkiler ile oluşturulan austenite-martensite faz

dönüşümünün kristalografik özellikleri X-ışınlan geri yansımalı Laue metotları ile çalışıldı.

Alaşımda austenite-martensite faz dönüşümünün izotermal olduğu ve dış etkiler ile

değişmediği görüldü. Numunelerin yüzeyinde Lath türü martensitlerin meydana geldiği

gözlendi Numunelerin kristal yapılann örgü parametreleri dış fiziksel etkilere bağlı olarak

değiştiği ve alaşımın martensite alışım düzleminin ise dış fiziksel etkilere bağlı olarak

(225)a ve (259)a’da olduğu bulundu

Keywords

Auetenite, Martensite, Örgü Parametresi, Alışım Düzlemi İzotermal

References

• Borgenstam, A. And Hillcrt, M., 1997, "Activaüon Energy for Isothermal Martensite in Ferrous Alloys". Acta Metall, 45, pp 651.
• Chang. S.N. and Meyers. M. A., 1988, "Martensitic Transformation induced by a Tensile Stress Pulse in Fc-22.5%Ni- 4%Mn Alloy", Acta Metall, 36, pp 1085.
• Cullity. B.D , 1967., "Elements of X-Ray Diffraction", Addisson-Wesley Publishing Company, Inc, London.
• Durlu, T.N.,1974 "Some Aspcncets of the Martensitic Transformation in Fe-Ni-C Alloys, Doklora Tezi, Oxford Ünv., Oxford.
• Easterling,K.E. and Tholcn, A.R., 1974, "On the Graurth of Martensite in Steel", Pergaman Press. Oxford.
• Kajiwara, S., 1981, "Morphlogy and Crystallography of the Isothermal Martesitc Transformation in Fe-Ni- Mn Alloy", Philosophical Magazine A, 43, pp 1483.
• Olson, G B. and Cohen, M., 1976, "A General Mechanism of Martensitic Nucléation, Part III. Kinetics of Martensitic Nucléation", Metallurgical Transactions A, 7, pp 1915.
• Nishiyama,Z., 1978, "Martensitic Transformation", Acedemic Press, London. Wakasa,K 1981, " Crystallography and Morphology of Ferrous Lath Martensite", Melllographv. 14. pp 49
• Wakasa, K. and Wayman. C.M., 1981, "Isothermal Martensite Formation in an Fe-20%Ni- 5%Mn Alloy". Metallograph, 14, pp 37.
• Wakasa, K. and Wayman. C.M., 1981, "The Morphology and Crystallography of Ferrous Lath Martensite Studies of Fe-20%Ni- 5%Mn-I Optical Microscopy", Acta Metall, 29. pp 973.
• Yang, D.Z., Sandvik, B P J. and Wayman, C M., 1984, "On the Substructure of Athermal and Isothermal Martensites Formed in an Fe-21%Ni- 4%Mn Alloy", Metallurgical Trnnsocations A, 15, pp 1555.