本研究主要探討冷軋FCC相鐵鈀合金的織構與微結構之發展。由於冷軋製程可以使材料具有優選方位與較小的晶粒尺寸，因此，有利於退火後所得到硬磁性FCT相鐵鈀薄片具有較佳的矯頑磁性。在冷軋製程中，FCC相鐵鈀合金厚度的減少率分別為50%及88%。再利用X-ray diffraction (XRD)與electron backscatter diffraction (EBSD)分析FCC相的鐵鈀合金的織構與微結構。
實驗結果發現試片厚度減少從50%到88%，{220}優選方位逐漸增加，並且Brass {110}<112>和Goss {011}<100>方位強度隨之增加，而Copper {112}<111>方位強度不會消失反而增加。EBSD所分析的方位分佈函數(orientation distribution function, ODF)之結果與XRD所分析的ODF相似，因此以EBSD分析微結構是可信的。在微結構方面，雙晶密度在軋延之前(0%軋延量)為46%。在50%軋延量時，雙晶密度為12%，Deformation Twin、Transition Band和Deformation Band等微結構被觀察到。而Micro-shear bands、Deformation Twins和Deformation Bands等在88%軋延量時亦被觀察，雙晶密度增加為20%。平均晶粒尺寸(28.55 ~ 3.43 μm)隨著減少率(0 ~ 88%)增加而減少。除此之外，Dislocation Slip、Mechanical Twinning和Shear Banding被認為是88%減少率的變形機制。Goss方位的Shear Bands 推測是導致Goss成份和Copper成份上升的原因。

This study focused on observing the evolution of texture and microstructure in the face-centered cubic (fcc) disordered phase of FePd alloys during cold rolling. Cold rolling can produce preferential orientation and small grain size. Therefore, the hard magnetic properties, such as coercivity, of the face-centered tetragonal (fct) ordered phases of FePd alloys will be improve after the fct phase transformation annealing.
Here, fcc phase of FePd alloys are cold rolled to moderate deformation (50% reduction) and high deformation (88% reduction). Then, the evolutions of texture and microstructure of fcc FePd alloys for 50% and 88% reduction would be analyzed by using x-ray diffraction (XRD) and electron backscatter diffraction (EBSD) techniques.
As the result of texture analysis form 50% to 88% reduction, preferential orientation of {220} is gradually increasing during cold rolling from 50% to 88% reduction. In addition to this, orientation densities of Brass {110}<112> and Goss {011}<100> are increasing. Copper {112}<111> is not diminished instead of increasing. On the other hands, the orientation distribution functions (ODFs) for 50% and 88% obtained by EBSD compared with that by XRD. Therefore, the results of microstructure analysis by EBSD are confident with these by XRD. For the microstructure analysis, annealing twins of <111>60o is widely observed as 46% fraction of twin at the reduction 0%. For 50% reduction, twin fraction has decreased to 12%. Deformation twins, deformation bands and transition bands have been observed at 50% reduction. For 88% reduction, twin fraction has increased to 20%. Micro-shear bands, deformation twins have been observed at 88% reduction. Average cell size decreases as 28.55 to 3.43m during cold rolling from 0% to 88%. In addition to those, dislocation slip, mechanical twinning and shear banding are considered to be the deformation mechanism after 88% cold rolling. Occurrence of Goss-oriented micro-shear bands are supposed to be the cause of increasing of Goss and Copper components at 88% reduction.

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