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Research on the Crack Forming and Control of Centrifugal Cast High Speed Steel Rolls Xilan Feng1, a, Zhiqiang Jiang2,b and Jinfa Shi2,c 1 Department of Mechanical Engineering, Zhengzhou Institute of Aeronautics, Zhengzhou 450015, China 1 Department of Industrial Engineering, Zhengzhou Institute of Aeronautics, Zhengzhou 450015, China a jwen912@zzia.edu.cn, b newroom@zzia.edu.cn, c cad@zzia.edu.cn Keywords: High speed steel roll; Centrifugal casting; Crack; Modification; Variable speed casting Abstract.
The structures and properties of HSS roll modified by potassium and rare earth were improved.
Factors affecting the crack of HSS rolls Influence of HSS material The crystallization characteristics and chemical compositions of cast alloy have obvious influence on the hot crack.

Tool parting distance, rake angle and edge radius affects surface integrity.
A positive correlation was obtained between these factors and negative residual stress.
It consists of geometric modeling of tool and workpiece and assigning material properties as per Johnson-Cook material model.
Due to these factors higher compressive residual stresses are induced on machined work surface when the cutting speed is increased from 150 m/min to 250 m/min, for all chosen rake angles.
Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 2011, 225, 1407-1417.

As we all know, the microstructure is affected by many factors, such as deformation temperature, strain rate and et al.
Zhao, Microstructure and mechanical properties of AZ91D magnesium alloy prepared by compound extrusion, Mater.
Meng, Microstructure evolution and mechanical properties of Mg-11Gd-4.5Y-1Nd-1.5Zn-0.5Zr alloy prepared via pre-ageing and hot extrusion, Mater.
Umakoshi, Effect of long-period stacking ordered phase on mechanical properties of Mg97Zn1Y2 extruded alloy, Acta Mater. 58, 6282-6293 (2010)
Zhang, Microstructure, texture evolution and mechanical properties of multi-directional forged Mg-13Gd-4Y-2Zn-0.5Zr alloy under decreasing temperature, J.

Modification of the ø26 mm round bars rolling technology with accelerated cooling, affect the reduction of average austenite diameter, which cause improving impact resistance of the final product.
Due to this, the correct strength and plastic properties of finished products cannot be assured.
Unification on the cross section and reduction of the austenite grain size should causes uniform mechanical parameters and increase impact resistance.
Production of the ø26 mm round bars in proposed technology, with one accelerated cooling section during rolling enables estimation of final product with slightly higher mechanical properties.
[2] Koczurkiewicz B., Korczak P., Dyja H.: Assesment of the strain history impaction the after rolling microstructural parameters and mechanical properties of steel. 5th International Conference Form.

Consequently, these morphological changes affect primarily the thermal conductivity and eventually the Young' Modulus which are the key physical properties of this material group.
The required properties for TBCs are low thermal conductivity, high thermal expansion coefficient, thermal shock resistance, as well as phase and morphology stability under long-term and high temperature service conditions.
Thermo mechanical tests of these TBCs revealed significant property changes due to their limited phase and microstructure stability and low sintering resistance [3,4].
For these systems at least two factors contribute to a reduced thermal conductivity: firstly, thin films have been reported to exhibit lower thermal conductivities than the respective bulk materials, and secondly, additional boundaries are incorporated perpendicularly aligned to the heat flux.
High temperature ageing changes thermal and mechanical properties of TBCs.

The influence of the mass ratio of W and Cu on the structure and properties were investigated.
However, the highest relative density of W-Cu composites was only 75.0%, which was caused by two factors.
Influence of activators on properties.
Zheng, et al., Properties of W–Cu composite powder produced by a thermo-mechanical method.
Roderick, The physical properties of liquid metals, Clarendon Press, Oxford (1993)

Typically, WT contains a mixture of aromatic hydrocarbons, phenols, and terpenes, which contribute to its hydrophobic properties.
The effectiveness of these methods depends on various factors, including the environmental conditions, the quality of application, and the properties of the chosen materials.
The main goal is to determine whether WT can effectively reduce the water absorption in concrete, without affecting its mechanical properties, and incentivizing further studies to investigate the service life of such materials, aiming to provide a greener alternative for the construction industry.
This range aligns with the decomposition of aromatic hydrocarbons, which are known for their hydrophobic properties.

The higher steam parameters (operating temperature and pressure) of the new plants require new materials with improved long-term high-temperature properties.
The new ferritic super heat-resistant Cr-Mo steels (always mass%) have been recognized as an alternative for widely used high-strength austenitic stainless steels because of their favorable physical properties (thermal expansion and heat conductance) and lower price[4,5].
Therefore, under service conditions (elevated temperature and pressure) pronounced microstructural changes occur, leading to the degradation of long-term properties.
During exposure to elevated temperatures and creep stress, pronounced microstructure evolution occurs (recovery, grain and subgrain coarsening, precipitate coarsening), which deteriorate the mechanical properties.
Factors affecting a coarsening rate of MX are interfacial energy, γ, diffusion coefficient, D , solubility of particle in the matrix, ∞C , and molar volume in the particle, mV , in the case of a constant temperature.

Sealing performance analysis of Cap seal rings in the Stirling engine piston rod Chang Jun1,a 1School of Mechanical Engineering, Lanzhou University of Technology, Lanzhou city, Gansu province, China achangjun0931@163.com Keywords: Rod seal; cap seal structure; stress analysis Abstract: When the Stirling engine piston rod for reciprocating motion at a high speed under dry friction conditions, the temperature fall or pressure drop is mainly caused by uneven sealing ring deformation, increased wear and sealing performance fall.
Introduction Stirling engine as key components of plate type heat generators system, its performance directly affects the working efficiency of Plate type heat power generation system[1].
Because the cap seal is under the condition of dry friction of reciprocating dynamic seal, so under harsh working environment, the factors for influence effects of cap seal is complex.
Cap seals installation shematic diagram The stress analysis of cap seal in theory under the dynamic seal condition Structure and material properties of PTFE Teflon (PTFE) is a thermoplastic material, which high molecular weight, high crystallinity, its molecular structure is shown in figure 1.1.

SINS Transfer Alignment Based on Robust SDRE Filter Dayong Wang , Ping Sun, Peng Jianyi 1, Xing Huo Gang XU2, b Wuhan Mechanical Technology College,Wuhan Hubei , 430075, China 1email: pjyxp@163.com Keywords: SINS; alignment; SDRE filte Abstract.
Initial alignment is a fatal technology for SINS, and it affects the navigation performance of the system directly.
Robust SDRE filter Consider a smooth nonlinear uncertain system described by continuous-time equations of the following form [6] : (3) (4) where is the state, is the measured output, and , are process and measurement noises with unknown statistical properties, which stand for exogenous disturbance inputs.
Multiple Fading Factors Kalman Filter for SINS Static Alignment Application.