ZHANG Yan
,
CUI Qi-peng
,
SHAO Fu-qun
,
WANG Jun-sheng
,
ZHAO Hong-yang
钢铁研究学报(英文版)
In hot-dip galvanizing process, air jet wiping control is so crucial to decide the coating thickness and uniformity of the zinc layer on the steel strip. The mathematical models developed predict the zinc coating thickness as a function of pressure and shear stress. The required pressure and shear stress profile on the strip surface were calculated using regression analysis, and carried out using numerical simulation as FLUENT, a finite element analysis software. The influences of the outlet pressure, the nozzle to strip distance, the slot opening, the edge baffle plate, as well as the tilting angle of air knife were discussed. Combining with these results and regression analysis on the practical data, four first-order polynomial multi-parameter models were established for different targeted coating thicknesses with better regression coefficients. The validated model was used to carry out sensitivity analysis to determine the favorable controlling regime for the air jet wiping process.
关键词:
hot-dip galvanizing
,
air knife
,
air jet wiping
,
numerical simulation
,
coating thickness
ZHANG Yan
,
SUN Yu-fu
,
ZHAO Jing-yu
,
GUAN Shao-kang
钢铁研究学报(英文版)
Microstructure and high-temperature dry sliding wear at 600 ℃ in ambient air of austenitic heat-resistant steel ZG40Cr25Ni20 with different contents (mass percent) of Al (0 to 710%) have been investigated. The results show that microstructures of 468% and 710% Al addition content consist of the matrix and reinforcement of intermetallic compound γ′ and carbide, while microstructures of ZG40Cr25Ni20 without Al and with Al of 168% are absent of γ′. Higher wear resistance than the original ZG40Cr25Ni20 alloy is achieved in alloys with higher content of Al under the same high-temperature wear test condition. The wear rates of Fe-25Cr-20Ni-710Al and Fe-25Cr-20Ni-468Al are only 2083% and 4583% of that of Fe-25Cr-20Ni, respectively. Heat-resistant steels with higher contents of Al (472% and 710%) have higher hardness than those with lower contents of Al (168% and 0). Wear mechanisms of ZG40Cr25Ni20 are considered as severe plough plastic deformation and slight adhesive. However, wear mechanisms of Fe-25Cr-20Ni-468Al are light micro-cutting and oxidation-wear, while that of Fe-25Cr-20Ni-710Al are severe adhesive transfer and oxidation-wear.
关键词:
austenitic heat-resistant steel
,
Al
,
microstructure
,
high-temperature sliding wear
,
mechanism
Journal of Materials Research
The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.
关键词:
room-temperature
白宣羽
,
汪渊
,
徐可为
稀有金属材料与工程
采用磁控溅射方法在Si(111)基片上沉积Cu-Zr/ZrN薄膜体系作为扩散阻挡层.通过比较Cu-Zr/ZrN薄膜体系和三元非晶(Mo,Ta,W)-Si-N的电阻率,同时比较Cu-Zr/ZrN薄膜体系和Ta,YaN的硬度,说明作为扩散阻挡层的材料的选取,应从整体性能上考虑,而不能仅仅考虑热稳定性等单一指标.
关键词:
非晶
,
电阻率
,
纳米压入
,
硬度
Philosophical Magazine
The error of Equation (15b) in my article [Z.D. Zhang, Phil. Mag. 87 (2007) p.5309] in the application of the Jordan-Wigner transformation does not affect the validity of the putative exact solution, since the solution is not derived directly from that equation. Other objections of Perk's comment [J.H.H. Perk, Phil. Mag. 89 (2009) p.761] are the same as those in Wu et al.'s comments [F.Y. Wu et al., Phil. Mag. 88 (2008) p.3093; p.3103], which do not stand on solid ground and which I have sought to refute in my previous response [Z.D. Zhang, Phil. Mag. 88 (2008) p.3097]. The conjectured solution can be utilized to understand critical phenomena in various systems, whereas the conjectures are open to rigorous proof.
关键词:
3D Ising model;exact solution;conjecture;critical phenomena;ferromagnetism;magnetic phase transition;model;analyticity
