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Introduction The increasing use of aluminium alloys in the manufacturing of automotive parts has pushed car manufacturer to look for new processes to obtain better technological performances than the traditional castings (which usually imply defects, dendritic microstructure and poor mechanical properties) [1] and higher flexibility and lower costs compared to forging [2].
In case of axi-symmetric parts, flowforming has become an attractive solution, since the high localization of the strains allows significant reduction of the loads applied on the tooling, high mechanical properties of the deformed part, and excellent wall thickness distribution [3].At present the knowledge of this process mechanics still shows several gaps and standardized procedures aimed to the process design have not been developed yet, except for specific casesthat can be hardly widespread in industrial world, in which the choice of optimal process parameters remains an “art”[4].
This work is the follow-up of two previous studies on the same topic: in the first one [13] an analytical model for the roll-part contact area was proposed, while in the second one [14] the influence of heat treatment on microstructure and mechanical properties was experimentally investigated.
Gleeble 3800™ thermo-mechanical simulator was used to perform the hot compression tests suitable investigate the material mechanical characteristics.
On the other hand, the rotation speed n and the feed rate f can be considered as second-order factors, for a given fr value.

Based on the results of testing the samples, mathematical models have been developed which describe the dependences of the physical and mechanical properties of the cement com-posite material samples on the fraction of waste and water-cement ratio.
Variation intervals of factors x1 and x2 Factors Variation levels -1 0 +1 The proportion of powdered optical discs waste from the filler weight (factor x1) 0 0.25 0.5 Water-cement ratio (W/C, factor x2) 0.45 0.55 0.65 Dispersion of the mixture components and compaction during molding was carried out manually.
Results and Discussion Based on the data obtained as a result of testing the samples, mathematical models have been developed that describe the dependences of the physical and mechanical properties of the samples of cement composite material on the above factors.
The possibility of using the maximum possible amount of waste without significant deterioration of the physical and mechanical properties of fine-grained concrete is noteworthy.
The physical and mechanical properties of the cement composite material with a filler in the form of powdered optical discs

Biomaterials that are used for bone tissue engineering need to fulfil many requirements that are closely connected to the biofunctional properties, physical and chemical characteristics, mechanical properties, interactions with the physiological environment.
An important properties for polymeric based composite it’s the porosity, who affects their mechanical properties, degradability, dimensional stability and have the potential of compromising not only the function of the implant but also can affect the biocompatibility [3].
For these biomaterials, the degradation of the collagen matrix is very important because the rate of degradation (loss in mechanical properties) should be tailored with the rate of tissue generation [1].
We use β-tricalcium phosphate and hydroxyapatite as bioceramics for reinforcing the collagen matrix because we want to see how the bioceramics type will affect the biodegradation properties of the composites [6, 7].
Future studies will be made in order to optimise the composition of the composite materials, analyse the mechanical properties and the biocompatibility of the experimental composite materials developed.

This can lead to detrimental chemistry variations, which can have negative impacts on physical and mechanical properties.
While these changes often yield a material that falls within the AMS 4911 specification, the impact on mechanical properties can be intolerable.
Thus, in order to ensure part-to-part repeatability with known mechanical properties, it is important to develop processing parameters that yield consistent chemistry and therefore consistent properties.
Either scenario can be detrimental to chemistry and mechanical properties.
• Melt pool size, temperature profile, and geometry are likely the key factors in determining aluminium loss during electron beam deposition processing.

Introduction NBR has good oil resistance, water resistance, air tightness and heat resistance properties, mainly used for the production of oil washers, gaskets, oil seal materials，which have been widely used in the aerospace field.
Owing to the influence exerted by the mechanical stress, heat and oxygen in the air, environmental media and other factors, the NBR’s compression rate decreases relatively, Such as materials gradually sclerosis and crack, the variation of physical and chemical properties, mechanical properties, electrical properties change and so on, which leading to the production of all kinds of security hidden danger even accidents.
So the rubber material aging behavior in-depth study of the various countries' cause extensive attention of researchers.which resulting to the loss of NBR’s excellent mechanical and sealing properties.
Owing to the natural aging test’s long period, and NBR’s effect factors can't be researched separatly, a perfect experimental result are not able to get in a short time.
Mechanical rejuvenation in polymer glasses：fact of fallacy[J].

Materials which possess superior properties, brittle are difficult to machine using conventional methods.
So that these factors are taken as input process parameters.
Four factors were chosen for the present study among which one factor with two levels and all the other factors with 3 levels.
Yi is the normalized asset value of its alternatives, where g represents maximization; (n-g) represents minimization with considering all properties
A2 (Laser power at 2 kW), B3 (Gas pressure at 1 bar), C3 (Focal length at 1.2 mm) D1 (cutting speed at 1300 mm/min) Conclusions The experiments were conducted as per Taguchi’s L18 orthogonal array and multi-objective optimization was performed using MOORA · Laser power was observed to be the most significant factor affecting the kerf width followed by focal length, gas pressure and cutting speed

Effects of Riyadh cement industry pollutions on some physiological and morphological factors of Datura innoxia Mill.
Zheng, Mechanical and thermal properties of polypropylene (PP) composites filled with modified shell waste.
Darwish, Characterization of bio-filler derived from seashell wastes and its effect on the mechanical, thermal, and flame retardant properties of ABS composites.
Darmayanti Mechanical properties of seashell concrete.
Neville, Properties of Concrete, Longman London, 2011 [20] B.

CMC are used in many industries, for example, automotive, aircraft, space, chemical and energy industries, shipbuilding, oil- production and refining due to the possibility of combining different properties in one part.
St/Al clad composites are characterized by a combination of high mechanical properties and toughness, good corrosion resistance, high thermal and electrical conductivity, and find application in automobile and shipbuilding industries as well as in the manufacturing of the building panels and bearings [1–3].
For this reason, study of the influence of various factors on the bond strength between dissimilar materials is actual scientific direction.
Jafarian, Effect of thermal tempering on microstructure and mechanical properties of Mg-AZ31/Al-6061 diffusion bonding, Materials Science and Engineering A, 666 (2016) 372–379
Taherizadeh, Effect of Roughness and Surface Hardening on the Mechanical Properties of Three-Layered Brass/IF Steel/Brass Composite, Trans.

Thus, it is crucial that RCS should have proper mechanical properties to provide the cores made from it have enough strength to prevent core crack during the casting process.
Some researches studied relevant factors affecting to quality and improve properties of RCS.
There were 7 factors of interest in the experiment.
Type and properties of sand and resin under study.
Factors used in the CCD and their levels.

Because design parameters are uncertain, different design parameters of the mechanical structure have different effect, we can determine the reliability of the design parameters to affect the reliability of mechanical structure by sensitivity analysis and the reliability sensitivity analysis has become an important part of the design.
It has a good damping property, saving materials, reducing weight and so on.
In engineering design, variable cross-section components are widely used due to its good mechanical property, such as cantilever brackets, circular hollow vertical rod, etc.
Example In general, if the geometric dimensions and material properties are normal distribution random variable, deflection and material properties are mutually independent random variables.
In the integration process from analysis to design, we can grasp the important design factors, and understand the design, manufacture, basic data statistics and so on, the simplification is an important design parameter.