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Duflou1,d 1Department of Mechanical Engineering, KU Leuven, Belgium avitalii.vorkov@mech.kuleuven.be, brichard.aerens@hotmail.com, cdirk.vandepitte@mech.kuleuven.be, djoost.duflou@mech.kuleuven.be Keywords: multi-breakage phenomenon, springback, high-strength steel, finite-element modeling, air bending Abstract.
Fig. 1 – Scheme of the multi-breakage effect: splitting or „breaking“ of the contact surface The calculation of springback is a very challenging task, because many factors affect the part during and after bending [1].
(1) Where: ε: equivalent plastic strain K: strength coefficient n: hardening exponent Table 1 – Material properties of Weldox 1300 [6] Density [kg/m3] Poisson’s ration μ [-] Initial elasticity modulus E [MPa] Plane strain elasticity modulus Eʹ [MPa] K [MPa] n [-] 7800 0.3 2e5 2.2e5 1770 0.06 Fig. 5 – Overview of loading scheme and finite-element mesh Fig. 6 presents the results (contact pressure on the plate) of the finite-element computations.

On a side note, the inclination angle during manufacture affects not only the surface quality, it has also an immense influence on the tensile strength and a measurable impact on the fracture toughness of the material [11-13].
Major changes in the surface morphology were evident based on the present thermal environment, governed by the surface inclination and the related factors, i.e. proximity of already solidified areas, interaction with the loose powder particles, as well as irradiation energy and pathway (Figure 4).
Journal of Advanced Mechanical Design, Systems, and Manufacturing 8 (2014) JAMDSM0009
Van Humbeeck (2010) Part and material properties in selective laser melting of metals.

Experimental Study on Wear-resistance of machined surface in High Speed Milling Aviation Aluminum Alloy Xiuli FU 1, a, Xiaoqin WANG 1, b, Yongzhi PAN 1,c and Yang QIAO 1,d 1Department of Mechanical Engineering, University of Jinan, China ame_fuxl@ujn.edu.cn, bme_wangxq@ujn.edu.cn, cme_panyz@ujn.edu.cn, dme_qiaoy@ujn.edu.cn Keywords: Aluminum Alloy 7050; Wear Quantity; Friction Coefficient; Wear-resistance Abstract.
The wear-resistance performance of machined surface is an important factor in the evaluation of surface quality and precision in aerospace manufacturing industry.
These results indicated [7, 8] the work hardening, surface roughness and residual stress in different machining conditions had significant effect on wear-resistance properties of machined surface.
Material Property In aerospace industry aluminum alloy 7050-T7451 was usually fabricated into large-scale integrated frame parts with thin-walled and complicated structures.
The results demonstrated that wear-resistance can be directly affected by work-hardening, and the higher of degree of work hardening is, the better its wear-resistance is.

On the Control System for Blank-holder Force in Deep Drawing Based on Self-tuning Fuzzy-PID Controller Chun-Ping CAO a, Yu SUN b School of Mechanical Engineering, Nanjing University of Science & Technology, Nanjing, China ,210094， a ccp_alice@163.com,b sunyu@mail.njust.edu.cn Keywords: Fuzzy control, PID Control, Blank-holder Force, Simulation Abstract: Blank-holder Force (BHF) control technology is an important guarantee for the quality of parts forming.
If the blank-holder force is too large the wrinkling can be avoid, but the tearing tendency is increased as well as the possibility of surface damage to die and sheet metal, which will affect the quality of metal shaping and die life.
Blank-holder force is one of the key parameters affecting the process of sheet metal stamping.
The simulation has been done to prove that the method is effective in improving the dynamic property and decreasing the steady state errors of the BHF.
The corresponding numeric factor is as following, max max 5 10 0.5, 5 5 1 e ec k n e k m ec = = = = = = ; max 3/1 3 up u k l = = = , max 3/1 3 ui u k l = = = , max 1 1 1 udk u l= = = 。

However, film obtained with triethanolamine had low thickness, but showed good corrosion properties.
This follows from the high-frequency (HF) range of impedance diagrams, which reflects the outer layer properties, while the LF range characterizes the inner layer properties.
Mechanical properties of the CP-Ti sample nitride in the solution of ammonium chloride (10 wt.%) and ammonia (5 wt.%) at 750 °C during 5 min.
Han, Mechanical properties of Ti(C0.7N0.3) film produced by plasma electrolytic carbonitriding of Ti6Al4V alloy, Appl.
Mukhacheva, Effect of Compositions of Active Electrolytes on Properties of Anodic Carburization, Prot.

Introduction TP304 was widely used in the heating surface of pipes in station boiler with working temperature 600˚C, as it holds superior mechanical property and steam oxidation resistance in high temperature.
It proves to be one of the principle factors that endanger the security of SC or USC.
Once oxide film forms, whether oxidation process continued or not, was determined by two factors, interface reaction rate and diffusion rate of reacting matter crossing the oxide film [7].
This is the key factor that shot blasting treating TP304 exhibited slower steam oxidizing rate than original TP304.
According to previous documents [5], the difference of diffusion rate between Fe and Cr element played an important factor to affect the phase composition in the external oxide film.

Too large clearance may make steel cuttings between shear edges, which affect shearing quality. 1) Modeling of up shear edge The width of shearing rolled piece based on design goal is 700-1400mm, and the length of shearing edge is 1.3 times of width of panel, 1800mm.
Therefore, the mechanical strength should be high to satisfy mechanical motion feature.
Its mechanical property is worse than that of closed rank.
The minimal safety factor 5.4 is greater than the general design standard.
Reference: [1] Johnson R C.Mechanical Design Synthesis with Optimization Applications, Van Nostrand Reinhold Company,1971

The occurrence of accidents and the subsequent destruction of metal structures is associated with many factors, but almost always due to the formation of damage in the elements of these structures According to the normative documents [1], defects and damage of elements of steel structures depending on the responsibility of a particular element to ensure the operability of the structure as a whole, as well as the degree of danger of defect or damage, are divided into three categories: - the category Ad includes defects and damages of especially responsible elements and connections which pose direct danger for destruction of a steel design as a whole; - category Bd includes defects and damages that do not pose a direct danger to the destruction of the steel structure at the time of detection, but may subsequently cause damage to other elements (assemblies, joints) and may be transferred to category Ad during further operation; - category Cd includes defects and damages that do not belong
In particular, in his work VV Kotelnikov [5], considers methods and devices of thermal control, based on the fact that during the occurrence of deformations in steel structures, under the influence of mechanical stresses, a certain amount of energy (heat) is released, which is fixed by using an infrared camera, this method of thermal non-destructive testing is called passive and does not allow to detect defects after their formation.
A significant problem in conducting practical research and experiments was the property of metals to reflect infrared radiation.
The quality of thermograms is significantly affected by the degree of gloss of surface of the object, the high degree of gloss does not allow to obtain reliable data, to reduce the degree of gloss of the surface of the object requires a special coating with a high radiation coefficient.
[4] Zhengwei Yang, Xingyu Xie, Yin Li, Gan Tian, “Numerical Analysis of Influencing Factors and Capability for Line Laser Scanning Thermography Nondestructive Testing Technology in Chemicals Corrosion Defect Detection”, IOP Conference Series Materials Science and Engineering, 484 (1): 012026, 2019

Theoretical Formulas of the Ultimate Load-Bearing Capacity of T-Stub Joints The ultimate load-bearing capacity of T-stub joints is concerned with the dimension of T-stub flange, material properties, diameter and position of bolts.
The formulas of ultimate load bearing capacity of aluminum alloy T-stub joints can also be derived on the basis of this model, as long as the properties of aluminum alloy are considered.
The material properties in reference [1] are introduced in the parametric analysis on account of the insufficient data of tension test in reference [7].
Figure 3-b illustrates that the bolt position does not affect the collapse mechanism obviously.
Stress-strain Relationship and Physical-mechanical Properties of Domestic Structural Aluminum Alloy.

Once one surface galling failure case presents, dozens or even hundreds of RSTC always galling failure at the same time, which seriously affect drilling operation.
Based on numbers of galling drill pipes testing result, it’s found that chemical composition, mechanical properties, geometrical size and thread parameters of RSTC always met the requirement of API Spec 7-2:2008 and API Spec 5DP:2009 [2] standards.
Considering service environment and operation condition, it was concluded that the mainly related factors with surface galling damage included make-up torque, surface wear, thread compound, rearranging and tensile load.
In order to analyze the influence of these factors on surface galling damage of RSTC, full-scale experiments simulating field service condition were carried out in this paper.
The testing results showed that 60%~80% yield torque couldn’t resulted in serious damage or galling failure under the condition that thread parameters, geometry and material properties of RSTC and thread compound met the requirement of relevant standards.