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New Generation of ODS Alloys Petr Dymáček1,a*, Denisa Bártková1,2,b, Vít Horník1,2,c, Luděk Stratil1,d, Bohuslav Mašek3,e and Jiří Svoboda1,f 1Institute of Physics of Materials, Czech Academy of Sciences, Žižkova 22, 616 62 Brno, Czech Republic 2Brno University of Technology, Faculty of Mechanical Engineering, Technická 2, 616 69 Brno, Czech Republic 3COMTES FHT a.s.
A processing route of the ODS steels involves two steps: (i) the nano-composite powder containing matrix and yttria grains is produced by mechanical alloying (MA) and (ii) the powder is then hot consolidated.
The main disadvantage is the low creep fracture strain which represents a limiting factor for use in practice.
The results show that the grain-growing process in the new ODS alloys is significantly affected by the thermomechanical treatment, leading to the maximum grain size within 20-h annealing at 1200 °C.
The mechanical properties reported here are at room temperature and at 800 °C at low strain rates as a part of the ongoing alloy optimization process.

A Study on Normal Stress Distribution and Failure of Adhesively Bonded Joint under Cleavage Loading Xiaoling Zheng a, Mingsong Zhang b, Min You c, Haizhou Yu and Zhi Li College of Mechanical and Material Engineering, China Three Gorges University, Yichang 443002, China a zhengxiaoling@ctgu.edu.cn, b zms@ctgu.edu.cn, c youmin@ctgu.edu.cn Key words: epoxy adhesives; metal; stress distribution; cleavage; FEA Abstract.
Introduction It is well known that the cleavage strength is one of the main properties of an adhesively bonded metal-to-metal joint.
The early studies carried out by the authors ourselves dealing with one of the neglected factors that may affect the mechanical properties of the adhesively bonded joint is the treatment condition of the metal adherends before their recycling again [5-6].
The properties of the materials used in this study are taken as follows: pure copper adherends which elastic Modulus and Poisson Ratio is 110 GPa and 0.32, for steel 1045 as 209 GPa and 0.27, and for an epoxy adhesive as 3 GPa and 0.4 respectively.

Experiment that conducted by Panda [4] concluded that pyrolysis can be performed with or without catalyst where the catalyst affect the yield rate of the liquid fuel.
The chemical properties for diesel, TDF and WPDF used in the experiment are shown in Table 2.
Table 1: Engine specification Table 2: Chemical properties of test fuels Properties Diesel WPDF TDF Density [g/cm3] 0.841 0.771 0.923 Cetane Number 55 51[6] 42[8] Kinematic Viscosity @ 40 0C [cst] 3.05 2.149 5.1 Flash Point [°C] 84 72 44 Gross cal.
This factor make WPDF has comparable ignition delay compared to diesel fuel even though it has lower cetane number compared to diesel fuel.
This factor cause lower peak pressure when WPDF is combusted.

Model simplification When analyzing the finite element model of the platform, model simplification is to simplify the real structures according to the important problems and the main factors.
Their properties are defined by specifying the section shapes and parameters directly.
And its accuracy affects the subsequent numerical analysis result directly [5].
Fig. 6 The finite element model of the platform Conclusions The geometric model of the platform is established by using UG NX, and the material properties of each component are added according to actual working condition.
The finite element with equivalent mechanical properties is applied to simulate these components.

In order to study the physical and mechanical properties of recycled coarse aggregate, the grain diameter of the three kinds of tested recycled concrete were 5～20mm 、5～31.5mm、 5～40mm.
Then, the directly or indirectly affect of the different grain diameter on recycled concrete strength was measured.
Meanwhile, each group using fly ash and extra water modified recycled concrete, improving its interface transition zone and its mechanical properties and durability, making it meets its technology, environmental requirements and reducing the cost, making it develops to high-strength and high performance diretion.
Recycled concrete compressive strength is the main reason of the reducing regeneration and slurry between aggregate and in some regions with weaker.Microscopically speaking, the influence factors of recycled concrete strength is due to the existence of old cement slurry, new cement mortar can not with the original coarse aggregate better together, namely recycled coarse aggregate itself by the strength greatly weakened
Properties of Recycled Coarse Aggregate and Its Influence on Recycled Concrete[J].

Introduction About 60% problems of products exposed during using are caused by the process factors of manufacturing, so fault mechanism and the process quality evaluation model are of important engineering application value to ensure product quality and improve customer satisfaction.
While analytical method of Physics-of-Failure mainly takes reliability engineering as the theoretical basis and introduces physical and chemical methods to perform micro-mechanism analysis on internal and external factors of process quality.
To decrease the influence of subjective factors and make the result realistic [3,4], the process quality evaluation method is put forward based on MEP.
While the chopper’s speed of main shaft “v”, the back engagement of cutting edge “ap”, the longitudinal feeds “f” are the major factors that affect surface roughness of aluminum alloy box bodies.
Reliability prediction based on similarity between the products of mechanical products.

Many investigators have reported the effect of optical properties of pigments or dyes, clamp pressure, moisture content, carbon black concentration on the performance of the welded joint [1, 2, 3, 4].
Both process parameters and optical parameters had a great influence on seam weld properties [5].
The purpose of the analysis of variance (ANOVA) is to investigate which design parameters significantly affect the quality characteristic.
[3] Grewell, D. and Rooney, P. (2004), “Relationship between optical properties and optimized processing parameters for through transmission laser welding of thermoplastics”, Journal of Reinforced Plastics and Composites, vol. 23, No. 3
A. (2005), “Moisture Effects on Mechanical Performance of Laser-welded Polyamide”, Journal of Reinforced Plastics and Composites ,vol. 24, No. 11

Experimental Study on the Reheating Process for A356 Alloy in Thixoforming Pei Tang1,a, Deqing Mei1,b*, Honghua Zhou1,c, Zhuoxiong Sun1,d 1Department of Mechanical Engineering, Zhejiang University, Hangzhou, Zhejiang, 310027, China atangpeiys@sina.com, bmedqmei@zju.edu.cn, c200431390118@zju.edu.cn, d06jxlszx@zju.edu.cn Keywords: Induction heating; High frequency; Thixoforming; Microstructure Abstract.
Both of them will affect the quality of thixoforming seriously.
The eutectic microstructure must be remelted completely during the reheating process because fine Si particles in a eutectic microstructure have an adverse effect on die filling and mechanical properties.
So the first holding temperature and holding time are critical factors to improve the microstructure of the reheated billets.
(3) The first holding temperature and holding time are critical factors and have prominent effects to the microstructure of reheated billet.

Mechanical and Electrical Engineering, Harbin Institute of Technology, Harbin, China, 150001 Email: ycf1008@163.com Keywords: parallel machine tool, hydraulic system, feedback linearization, path tracking.
Moreover, most of these controllers demand some calculations of system dynamics, which may affect the property of real time for actual system.
Thereby, the dynamic model of mechanical system is briefly described for parallel machine tool.
Control Design Under the assumption of known dynamics structure, system geometric and inertia properties, and the perfectly repeating of desired load force.
Hence, a factor matrix can be utilized as (11) (12) where and are positive real values corresponding to sensitivity thresholds.

Wear damage is widely found in mechanical components, however it is difficult to eliminate it since there are many different types and mechanisms of wear.
A lot of factors affect it, e.g. mechanical force and displacement, materials, existence and the properties of lubricants, environments etc.
Another feature of wear damage is that it usually evolves very slowly when compared with other mechanical failures.
But it may be extended to further general wearing components because it deals with simple mechanical variables, a force and displacement.
Running-in period, the alteration of wear mechanisms and environmental effect can affect the behaviour of the depth increase.