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The prevailing Jiles-Atherton (J-A) model and Zheng Xiao-Jing-Liu Xing-En (Z-L) model are extensively used in modeling the magneto-mechanical effect on magnetization in ferromagnetic materials. In the J-A model, a fitting formula of magnetostrictive strain interms of stress and magnetization is adopted to model the stress effect on magnetostriction. However, the fitting formula is not in good accordance with the experimental results obtained by Kuruzar and Culllity. In order to solve this problem, a transcendental function tanh(x) is appropriately selected to describe the nonlinear magnetostrictive strain in the Z-L model, and it is found that the general formula of magnetostrictive strain is more effective to describe the nonlinear relation of magnetostrictive strain with stress and magnetization. Then, the modified law proposed by Jiles and Li is adopted to modify the Z-L model by Shi Pengpeng to describe the hysteretic behavior; nevertheless, the effect of Weiss molecular field, pinning energy and plastic deformation on magnetization are not taken into account, and the modified Z-L model can only describe the elastic stress effect on magnetization. In order to solve these problems above, a modified magneto-mechanical model is established by combining the magnetostrictive constitutive relationships of Z-L model with the modified energy conservation equation of J-A model, as well as taking the effect of elastic stress and plastic strain on the model parameters into account simultaneously. It is found that the predictions of proposed model here are in better accordance with the initial magnetization curves given by Jiles and Atherton and the hysteresis loops obtained by Makar and Tanner under different stresses and plastic deformation than those calculated by the J-A model and Z-L model. The correlation coefficients between experimental data and theoretical results calculated by the modified model are all over 0.98, which indicates that the modified model here is more effective than the existing model. A detailed study also performed to reveal the effects of the elastic tensile and compressive stress and plastic tensile and compressive strain on hysteresis loops, coercivity and remanence. The proposed model reveals that the area of hysteresis loop and coercivity increase nonlinearly with the stress and plastic deformation increasing, while the remanence decreases significantly; the effects of compressive stress and compressive plastic deformation on magnetization characteristic parameters above are more significant than those of tensile stress and tensile plastic deformation, which is consistent with the experimental trend. The proposed model can be used to quantitatively analyze the magneto-mechanical effect on the magnetization of ferromagnetism.

ZnS nanotubes with crossed-channels have been synthesized successfully using a hydrothermal method. A novel hydrothermal reaction of simultaneous solvent-oxidation-hydrolysis has been developed using Zn powder, H2O and NH2CSNH2 as reagents. TEM images show that each branch of the channels is about 400-500 nm long. The inner diameter is 55 nm, the outer diameter is 70 nm, and the interlayer spacing is about 7 nm. XRD data show that the product is well-crystallized in the cubic Sphalerite phase. The peak appears at 293 nm in the UV-Vis absorption spectrum, which is about 50 nm blue shifted from the bulk counterpart. The photoluminescence spectrum of ZnS nanotubes shows that the emission peak occurs at 409 nm when excited at 365 nm. Nanotubos de ZnS em forma de X foram sintetizados usando um método hidrotérmico. Uma nova reação hidrotérmica envolvendo hidrólise e oxidação simultâneas do solvente foi desenvolvido usando zinco em pó, água e NH2CSNH2 como reagentes. As imagens de microscopia de transmissão eletrônica mostram que cada segmento dos canais tem cerca de 400 a 500 nm de comprimento. O diâmetro interno é 50 nm e o externo 70 nm e o espaço entre as camadas é cerca de 7 nm. Dados de difração de raios (XRD) mostram que o nanotubo obtido apresenta boa cristalização na fase Esfalerita cúbica. A banda em 293 nm no espectro de absorção no ultravioleta-visível encontra-se deslocado para o azul em cerca de 50 mm em relação ao ZnS bulk. O espectro de fotoluminescência dos nanotubos de ZnS mostra que o pico de emissão ocorre em 409 nm quando excitado a 365 nm.