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Vanherckc Department of Mechanical Engineering, Katholieke Universiteit Leuven, Celestijnenlaan 300B, 3001 Heverlee, Belgium a Joost.Duflou@mech.kuleuven.ac.be, bAlexander.Szekeres@mech.kuleuven.ac.be, c Paul.Vanherck@mech.kuleuven.ac.be Keywords: force, prototyping, incremental Abstract.
Although it can improve surface finish and reduce production time by allowing larger vertical step sizes without affecting surface quality, large increases in tool diameter result in much higher forces and could become a limiting factor.
Micari: Influence of mechanical properties of the sheet material in single point incremental forming.

Evaluation of Surface Quality During Electrical Discharge Machining of Inconel 718 with Powder Metallurgy Electrodes Naveen Beri1,a, Sachin Maheshwari2,b, Chitra Sharma3,c 1Department of Mechanical Engineering, Beant College of Engineering and Technology, Gurdaspur, Punjab, India and Research scholar, University School of Engineering and Technology, GGSIPU, Delhi, India. 2Division of Manufacturing Process & Automation Engineering, NetajiSubhas Institute of Technology, Dwarka, New Delhi, India 3Department of Mechanical & Automation Engineering, IGIT, Kashmere Gate, Delhi, India anav_beri74@yahoo.co.in, bssaacchhiinn@gmail.com, cchitrabisht@rediffmail.com Keywords: EDM, surface roughness, powder metallurgy electrode, Taguchi methodology, EDS.
Tools manufacturing through PM process is an alternative tooling option for EDM electrodes where the desirable properties of different materials can be combined and a large number of tool electrodes can be made from a single die and punch assembly, resulting in an overall reduction of EDM tooling cost [3].
As the present study is focused on the performance of electrode it was decided to study all the two factor interaction effects between electrode type (A) and other parameters.
From Table 3 and the result of ANOVA it is clear that polarity, peek current and electrode type significantly affect the performance characteristics i.e Ra (P < 0.05).
C Pulse on time (µsec) D Duty cycle E Gap voltage (Volt) F Retract distance (mm) G Flushing pressure (Kg/cm2) H 1 -16.480 -14.199 -11.407 -12.134 -12.988 -12.444 -13.364 -13.218 2 -9.853 -12.752 -13.156 -13.760 -13.136 -13.387 -12.773 -12.877 3 -12.549 -14.937 -13.606 -13.376 -13.669 -13.363 -13.405 Delta 6.627 1.650 3.530 1.626 0.388 1.226 0.591 0.528 Rank 1 3 2 4 8 5 6 7 Fig.2 EDS of work surface machined with (a) CuW2080 (b) Cu electrode (-ve polarity, 4.0 amp. current, 50 µsec pulse on time, 0.7 duty cycle, 40 volts gap voltage, 2mm retract distance and 0.5 Kg/cm2 flushing pressure) Conclusions From the present experimental study it is concluded that improvement in surface quality of the machined surface with powder metallurgy processed electrode is possible and polarity, electrode type, peek current significantly affect surface roughness (Ra).

The die forging process is one of the widely used means characterized by highly improved mechanical properties and micro-structure texture at low cost.
Pre-die forging is the most important steps, because it mostly affect die-filling, die forging load and material utilization.
Fig. 1 Die-forging of connecting rod Table 1 Simulation Parameters Simulation parameter Value Environment temperature[℃] 20 Forging temperature[℃] 430 Die’s preheating temperature[℃] 200 Fraction factor 0.3 Heat transfer coefficient[N/sec/mm/℃] 11 Mesh number of billet 150000 Mesh number of upper die 250000 Mesh number of lower die 250000 Poisson ratio 0.3 Punch velocity[mm/s] 50 Stroke[mm] 46 Fig.3 Temperature field in die-forging of the connecting rod: (a)-(d) Fig.2 Distribution of connecting nodes of billet with dies Fig.4 Effective stress field in die-forging of the connecting rod: (a)-(d) Fig.5 Maximum principal stress field in die-forging of the connecting rod: (a)-(d) The billet temperature is kept below 500℃, and the distribution of the maximum temperature occurs on flash as is shown in Fig.3, so billet temperature distribution is reasonable.
Low temperature leads to hard flow ability, poor die filling and large deformation resistance, then increases die wear and reduces die life; High temperature leads to the oxidation of the surface and the forming large grain of the rod, which reduces the mechanical performance of the billet.
These results suggest that increasing the initial forging temperature can decrease the stress of dies significantly but not significantly affect the temperature of dies, this is help to extent dies life.

The shape and structure of a liquid droplet spreading over the solid surface is determined by the composition of the liquid, external conditions, and the properties of the surface layer of the substrate.
Under constant environmental conditions and properties of the surface layer of the substrate, the factors determining the dynamics of the spreading of a drop include surface tension, density, viscosity, physical and chemical processes that occur in a liquid.
In this regard, the problem was solved of studying the dynamics of hardening of the dispersion and identifying the degree of influence of physicochemical properties changes on it.
Desiccants affect the rate of formation and decomposition of hydroperoxides, change the amount of oxygen, which determines the kinetics of the formation of the mesh structure, and, consequently, the properties of polymer composites.
Ren, Comparative study on the effects of various modified admixtures on the mechanical properties of styrene-acrylic emulsion-based cement composite materials, Materials. 13 (2020). doi:10.3390/ma13010008

Further automation would be possible but would also affect negatively their economic efficiency.
Mass goods are arbitrarily packed – neatly or loose, stuck or slack patterns and with respect to their properties homogeneous or heterogeneous.
The first class arises from the context and it implies the performance indicators as critical success factor.
A study has been conducted to validate these assumptions about the qualitative and quantitative properties of transported goods [5].
The problems related to the manipulation of these objects, are mainly due to their high variability: shapes, dimensions, deformability, surface condition (smoothness or roughness and other materials' properties like magnetism).

Constitutive Equations for Hyperelastic Materials Constitutive equations, also termed physical relationships for a particular material medium, describe behaviour of a particular material as affected by a number of external factors.
It might be assumed that constitutive equations that describe the relationships between deformations and stresses or between deformations and energy for hyperelastic materials are obtained based on the equations of mechanical energy balance.
The choice of a material model depends on the factors that have the most essential importance to the behaviour of the medium.
For this reason, the constitutive equations define a subjectively selected model of material which describes actual behaviour (better or worse) in certain factors’ particular area of changes.
As for the elastic bodies without bonds properties of such a medium can be defined if there is a possibility to define the function W.

Application the Renewal Theory to Determining the Models of the Optimal Lifetime for Conveyor Belts Anna Grinčová1,a, Miriam Andrejiová2,b and Peter Grendel3,c 1Technical University of Košice, Faculty of Electrical Engineering and Informatics, Department of Mathematics and Theoretical Informatics, Nemcovej 32, 040 11 Košice, Slovak Republic 2Technical University of Košice, Faculty of Mechanical Engineering, Department of Applied Mathematics and Informatics, Letná 9, 042 00 Košice, Slovak Republic 3Driving School Grendel, SOŠ Automobilová, Moldavská 2, 040 11 Kosice, Slovak Republic aanna.grincova@tuke.sk, bmiriam.andrejiova@tuke.sk, cgrendel@grendel.sk Keywords: renewal model, cost function, conveyor belt, optimal lifetime of conveyor belt Abstract.
Optimal use of the conveyor belt in terms of its utility properties, sufficient care, and proper timing of servicing works using the top-class materials and tools have the crucial impact on the labour productivity, reduction of operating costs, and environmental friendliness.
This determination is carried out using the criteria that consider the impact of indirect factors, as well as reasons causing the conveyor belt wear and damage.
There are plenty of factors that affect the overall lifetime.
All factors can be mutually combined and together they cause failures of conveyor belts and thus reduce its lifetime.

Regarded in the production process as one of its factors, the job of maintenance must be part of the processes of performance management of this area and the company as a whole.
In everyday reality, aspects concerning the deadlines for production, market factors and strategic goals of organization, are all considered by managers as a whole, although not mentioned in the decision support systems.
In the process of plating internal temperatures are around 1112 ºF (600 ºC), more specifically in the continuous annealing oven (used to repair the mechanical properties of the sheet after the lamination process), and in the induction furnace (used for melting aluminum and zinc).
The very of the oven is one of the factors causing cracks in the walls, through which the liquid material leaks, and there is no way to know the extension of the cracks.
As it is determined that the failure came from maintenance, the downtime directly affects the availability of the line.

According to the measurement data statistics, analysis the influencing factors of indoor environmental pollution.
Take the indoor air respirable particulate matter as the research object, the PM10 were monitored in different period and we will analysis indoor PM10 concentration levels and its influencing factors.
In the certain conditions of particle property, particle scattering light intensity is proportional to its quality concentration.
Due to the low outdoor temperature and indoor without mechanical ventilation equipment, so can only switch or open the inside door to achieve the effect of ventilation.
Table 2 PM10 concentration statistical data comparison Buildings Outdoor PM10 (μg·m-3) Outdoor PM10 (μg·m-3) Temperature (ₒC) Humidity (RH%) Wind speed (m/s) Kindergarten Fog Haze 243.55 214.28 23 40 0.2 Sunny 18.00 20.50 29 45 0.3 Office Building Fog Haze 203.19 192.15 22 40 0.2 Sunny 25.00 35.00 30 50 0.3 College Classroom Fog Haze 106.37 162.86 20 40 0.2 Sunny 9.45 25.17 30 50 0.3 Seen from the figure data, the indoor PM10 concentration was not only affected by the indoor heating and ventilation technique, but also by the outdoor air environment.

Existing studies [1 - 4] have showed that if the grinding heat cannot be conducted and scattered timely and effectively, it will affect the surface quality and performance of workpiece due to the thermal damage.
(3) (4) (5) Where βw is shown as Eq. (6), and C1 is the factor for temperature solution taking into account the Peclet number (Pe), shown in Table 1.
(6) (7) Table 1 The factor C1 C1 1.06 0.76 Pe >10 0.2≤Pe≤10 <0.2 However, hf , Rws and r0 are assumed to be 10000,0.8 and 10 respectively in Eq. (1).
Tawakoli: High Efficiency Deep Grinding (VDI-Verlag and Mechanical Engineering Publications 1993)
Black, The Effect of Abrasive Properties on the Surface Integrity of Ground Ferrous Components, PhD Thesis, Liverpool John Moores University,1996