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The chemical composition of welding materials in the formation of a welded joint plays a decisive role-determines the presence of defects and mechanical properties.
Calculation of Melting Factors, Metal Deposit Factors and Losses The main efficiency and stability indicators for the arc welding process are: melting factor, metal deposit factor and losses.
Results and Discussion The resulting values of melting factors, metal deposit factors and losses are presented in Table 1.
Resulting values of melting factors, metal deposit factors and losses.
Concerning welding and technological properties, all electrodes for underwater "wet" welding are acceptable and suitable for underwater welding, but the best properties were recorded for UW-EZ-2 electrodes by BrocoUnderwater. 2.

Lee1 1Department of Mechanical Engineering, Graduate School, Mokpo National University, South Korea 2Department of Mechanical Engineering, Mokpo National University, South Korea ajsson@promecs.com, bilsookim@mokpo.ac.kr, ckimhyoung@mokpo.ac.kr Key words: bead geometry, empirical model, robotic arc welding, control and sensing Abstract.
Especially, real-time quality control in automated welding process is an important factor contributing to higher productivity, lower costs and greater reliability of the bead geometry.
Experimental Procedure The robotic arc welding process generally involves large number of process parameters that may affect product quality, productivity and cost effectiveness.
The mechanical properties and chemical composition of base metal are shown in Tables 2-3.
The selection of the electrode wire should be based principally upon matching the mechanical properties and physical characteristics of the base metal.

Helium is one of the most valuable gases with unique features and properties as well as widely used in various applications.
It is necessary to fine-tuning the carbonization conditions in order to obtain the desired permeation properties.
Despite of that, the type of the material used as a membrane is another factor that affecting the success of a membrane-based separation process for the purification of helium.
The properties of the membrane also can be influenced by process parameter such as carbonization heating rate in the range of 1-13oC [9-10].
In this study, the properties and performance of tubular carbon membranes (TCMs) that were fabricated by blending of PI/NCC has been studied.

The area changes of the minute central cavities were obtained, and combined with the internal stress state during the rolling process, the viewpoint that tensile stress in the three-dimensional directions is one factor that leads to cavity growth was expound.
Introduction Central cavity is one of the main defects in the workpiece of cross wedge rolling, which significantly weaken the mechanical properties of products.
Tensile stress in the all three-dimensional directions is one major factor that makes central cavity expand.
Conclusions Three-dimensional finite element models were established to simulate cross wedge rolling parts with a minute central cavity, the development of cavity is gotten and the reasons of cavity expansion was expounded by analyzing changes of the stress state , conclusions are as the following: (1) Tensile stress is one of the main factors leading to central cavity expansion, the higher the value of tensile stress, the longer the duration, the bigger cavity expansion
(2) Area reduction is a main factor that affects the development of the cavity. 30% area reduction is a turning point to expand or shrink cavity under the rolling condition in this paper

Well understanding of affecting factors and their interactions on surface finish is of crucial importance since it is one of the most specified customer needs.
Factors (input parameters) and factor levels are shown in Table 1.
Data analysis for surface finish Factors Effect Consideration.
ANOVA is employed to consider effects of main factors and factor interactions on temperature.
Plot of main effects is used to see which factors affect the sensitivity of the system.

Due to the fact that the kinetics of the rate of the chemical reaction at the interface is greater than the rate of solid-phase diffusion, the conditions and factors that ensure its occurrence are considered [10].
We see from (1) that the redistribution of nitrogen during nitriding directly depends on the diffusion coefficient and affects the diffusion time.
Experimental and tabular data for the pre-exponential factor are known.
[5] Heat Treatment Optimization and Nitriding Effects on Mechanical Properties of 32CrMoV12-10 Steel Fatih DEMİR1, Muhammed Bora AKIN1, Ahmet YARTAŞI1* 1Çankırı Karatekin University, Department of Chemical Engineering, Çankırı, 18100, Turkiye, 121
Kotova, Mechanical stability of materials.

These so called alloys have outstanding combination of high mechanical strength with good electrical conductivities [1,2].
Copper containing cast irons are of improved mechanical properties such as fatigue life and tensile stress endurance at elevated temperatures.
For simplicity, this physical model is dealt with using the following assumptions: (1) Mass transfer in liquid and solid is neglected; (2) The physical properties of the ribbons and the cooling wheel are constant, and are independent of temperature; (3) There is no gap between the ribbon and the cooling wheel, so that only heat conduction is considered. (4) The thermal resistance is neglected. 1.2 Heat transfer governing equation The initial temperatures within the ribbon and the cooling wheel are uniform at T10 and T20, respectively.
The enthalpy of the castings has great influence on the crystallization of rapid solidification of CuFe10 ribbons, which will result in major calculation errors if this factor is not considered.
The factors affecting the temperature distribution and the cooling rate are discussed according to the cooling rare function.

In addition, the covering flux does not float on the surface after being added in; in particular, in the process of mechanical agitation, it is easy to get inside the melt to form defects like inclusion.
The table 2 below presents the physical properties of the oxide formed by the added RE elements in the experiment of the research.
Factors affecting the yields of Y and MM elements are the oxidation of elements and their consumption due to the reaction with covering flux; the low yield of Zr may be due to the following two points: 1.
Yu: Study on the Microstructure, Properties and Deformation Techniques of Rare Earth Wrought Magnesium Alloys (A Dissertation Submitted for Ph.
Su: Microtructure, Mechanical Properties and Semi-Solid Microstructure Evolution of Mg-RE Alloy (A Dissertation Submitted for Ph.

Among recently developed techniques, ultrasound mixing efficiency was stated as one of the most important factors affecting the yield of the transesterification [3].
They used ultrasound after heating the oil and premixing with a mechanical stirrer.
The dark brown oil color proves that the properties of oil have changed after its repeated used for frying (the image is not shown).
Properties and composition of waste cooking oil Properties Composition Acid value (mg KOH/g) 0.97 Free fatty acid (% as palmitic) 0.44 Moisture content (%) 0.12 Saponification value (mg KOH/g) 201 Fatty acid composition (%) C12:0 C14:0 C16:0 C16:1 C18:0 C18:1 C18:2 C18:3 C20:0 Others 0.3 1.0 38.5 0.2 4.1 44.6 10.4 0.3 0.4 0.2 Effect of Methanol to Oil Molar Ratio on Percentage Conversion.
Catalyst amount is an important parameter that can affect the percentage conversion greatly.

The attention is paid to the assessment of the effectiveness of selected retardant protective substances applied to spruce wood that was thermally loaded for prediction of flammability properties and assessing the suitability of their application.
Introduction An important material used in building construction is also wood, because of its irreplaceable properties.
Wood is able to survive the centuries in a suitable environment, but as an organic material, when it is exposed to various harmful factors, such as e.g. climate impacts, biological agents, fires, mould, bacteria and other factors, it is subjected to degradation up to the loss of its lifespan and functionality.
In our paper we deal with an experimental assessment of selected retarding substances affect (HR-Prof, PLAMOSTOP D and D PLAMOSTOP-transparent), which were applied to the surface of solid spruce wood, and further thermally loaded with a radiant heat source.
Thickness of retarding coating (μm) 36 27 25 Adhesion – cross-hatch test (degree) 1 0 0 Evaluating the surface by application retarding substances treated wood with profile method To achieve the desired quality material characteristics is important to evaluate the surface properties of wood using the parameters of the roughness Ra (mean arithmetic deviation of the primary wood profile) and Rz (the full depth of the profile).