稀土元素Gd對NiMnIn磁驅(qū)動(dòng)形狀記憶合金相變和磁性能的影響.pdf

1、河北工業(yè)大學(xué)碩士學(xué)位論文稀土元素Gd對NiMnIn磁驅(qū)動(dòng)形狀記憶合金相變和磁性能的影響姓名：白麗娜申請學(xué)位級別：碩士專業(yè)：材料加工工程指導(dǎo)教師：張建軍20100301稀土元素 Gd 對 NiMnIn 磁驅(qū)動(dòng)形狀記憶合金相變和磁性能的影響 INFLUENCE OF RARE EARTH Gd ADDITION ON THE MARTENSITIC AND MAGNETIC TRANSFORMATION BEHAVIORS OF Ni-Mn

2、-In METAMAGNETIC SHAPE MEMORY ALLOYS ABSTRACT Ni50Mn34.5In15.5-xGd 、 Ni x 50Mn35In15-xGdx （x=0.1， 0.5， 1， 2） alloys were melting by vacuum arc furnace under. And the melting of the alloy after 900× 24h of ℃the diff

3、usion annealing quenched to 900× 2h in ice water ℃ . The martensitic and magnetic behaviors of the alloys were investigated by DSC、VSM、X-ray diffraction and Metallographic microscope etc. The experi -mental alloy ph

4、ase transformation and magnetic properties were studied. Experimental results show that rare earth element Gd on the magnetic drive NiMnIn shape memory alloy transformation temperature have a more significant effect on.

5、It can be greatly improved martensitic transformation temperature and alloy composition on the martensite transition temperature also has an influence. When the alloy in the amount of other elements remain unchanged, cha

6、nges in the content of In, when martensitic transformation temperature Ms, Mf, As, Af are increasing with the In content decreases ; Electron concentration in the 7.88-7.97 range, due to join the rare-earth alloy Gd make

7、s the electronic concentration, martensitic phase transfor -mation temperatures rise. By analyzing the X-ray diffraction pattern of the test alloys we found the parent organization for the phase mixture of austenite and

8、martensite at room temperature parent phase for the L21 body-centered cubic structure. Plus the shape memory alloy of rare earth Gd the main indicator of the location of diffraction peaks remain basically unchanged, incl

9、uding (220)、(222)、(400)、(332), indicating that additions of rare earth Gd may not change the structure of alloys is still austenite and martensite of the hybrid organization. But it created a new diffraction peaks, such

10、as the monoclinic martensite landmark 10M diffraction peaks (0010), (0210), (323) and so on. When the amount of Gd join to 0.5、 1、 2 at% , X-ray diffraction patterns of (220) diffraction peaks clearly split, indicating a

11、 new phase formation. When NiMnIn alloys add rare earth elements Gd , the alloy grain size and martensite lath has been significantly refined. Adding too many rare earth Gd would precipitate a new phase grain boundary. N