Finish turning is one of the key operations governing residual stresses below machined surface. The stress state depends on cutting conditions and selected tool system, i.e. macro geometry, edge preparation as well grade. However, wear often affects interaction between workpiece leading to severe modifications state. This work aims at investigating influence surface integrity in longitudinal a 15-5PH stainless steel. First, an experimental sensitivity study performed assess effect various...

Within the framework of welding steel components in pressurized water reactors, optimization weld pool penetration is a major issue. The thermal‐hydraulics molten can be driven by Marangoni flows at free surface. To compute these flows, liquid steel's thermophysical properties such as density ρ and surface tension σ are required. Such for austenitic vessel AISI 304L state scarce, even not available above 1800 °C, due to technological issues. viscometer temperature installation (VITI)...

This paper aims at introducing a new nodal-integration-based finite element method for the numerical calculation of residual stresses induced by welding processes. The main advantage proposed is to be based on first-order tetrahedral meshes, thus greatly facilitating meshing complex geometries using currently available tools. In addition, formulation problem avoids any locking phenomena arising from plastic incompressibility associated with von Mises plasticity and encountered standard...

Heat exchangers in new nuclear power generation plants are made of thin AISI 316L stainless-steel plates stacked together order to improve their efficiency and compactness. To ensure the assembly, global distortion those must be mastered minimized, mainly by predicting evolution residual stress field during manufacturing process chain. During machining, stresses redistributed reach another equilibrium state, leading a macroscopic part distortion. The main objective this work is study...

Surface integrity induced by longitudinal turning has been widely investigated in the literature. On contrary, few works have aimed at investigating surface during of geometric singularities such as fillet radii. This paper investigates generated while a radius martensitic stainless steel (15-5PH). The residual stresses, microstructure and mechanical properties characterized. Then, geometrical analysis revealed that chip removal mechanisms vary continuously along radius, which, consequence,...

The objective of this paper is to model the residual stress generation mechanisms induced during finish turning a fillet radius on 15-5PH steel shaft. model, based 3D thermo-mechanical equivalent loading method, used predict continuous variation stresses resulting from machined sections in radius. Finally, experimental tests are carried out compare numerical results with measurements made by X-ray diffraction some positions.

This work aims at developing an original numerical model to predict residual stresses induced by a grooving operation. is inspired the hybrid approach consisting in modeling thermomechanical loadings applied on machined surfaces. The paper will start present experimental investigations which have enabled define shape and intensity of during tool plunging second part this relates strategy. Finally stress profiles been made means X-Ray diffraction 15-5PH samples compared with results.

The modeling of cutting processes by the finite element method represents a great challenge for scientific researchers. Indeed, plastic strain and rate in induce high risk mesh distortion, especially models based on Lagrangian formulation which were first to be developed. To overcome this problem other formulations, such as Arbitrary Eulerian-Lagrangian (ALE), is combination classical formulations (Eulerian Lagrangian), have been Despite very interesting results simulation orthogonal...

Reaming is commonly used in industry to accurately enlarge and smooth the internal finish of a premachined hole. As holes are critical areas for fatigue resistance, this paper investigates influence some technological parameters, such as back taper tool holder flexibility, on surface integrity induced by reaming 15-5PH martensitic stainless steel. Residual profiles hole's geometry correlated cutting forces measurements thanks an original experimental set-up. This work highlights high...

Since grinding is often the last process of a manufactured part, caution has to be taken in order ensure integrity ground surface. Many authors have shown that few cases temperature can very high and therefore induce phase transformations. Thus, best way quality surfaces predict apparition these phases. This paper shows numerical simulations phases during are possible they gives good predictions An example using AISI 52100 bearing steel material for workpiece triangular heat flux model...

The prediction of welding residual stresses requires accurate account to be taken the couplings between heat transfer, metallurgy and stresses-strains in affected zone. To begin with, simulations for processes were performed at beginning 1970s. Since then, calculations have been compared validated with experimental measurements, major problem remaining is calculation time. Despite technological evolution computers, a 3D can last several days. avoid this difficulty, simplified approach...

Material removal operations such as turning or grinding are prone to generate very high temperatures at the tool/chip and tool/workpiece interfaces. These phenomena involved in studies concerning tools workpieces, their estimation is a key point for predicting damages. Temperature elevation main cause workpieces worsening because it generates residual stresses metallurgical modifications. It also linked wear of thermal fatigue thermally activated diffusion process. In this paper, first...

During grinding, commonly used as a finishing process, the integrity of part can be altered in many ways. Actually, generation high temperature level into workpiece generally causes burning marks, structural and metallurgical transformation, consequently influence built up residual stress. Therefore, control this process is great importance to ensure both precise dimensions small tolerance, required have good working parts. The relationship between metallurgic transformation stress field...

Finish turning is one of the key operations governing residual stresses functional surfaces. The stress state determined by thermomechanical loadings applied on machined surface over time. These depend cutting conditions and selected tool system (macro geometry, edge preparation, substrate, multi-layer coating…). However, this situation evolves time due to wear. At least two kinds parameters are modified: geometry (crater flank wear) tribological phenomena between (wear each layer coating)...

Grinding is one of the important metal cutting processes used extensively in finishing operation to get components desired shape, size and accuracy. A perfect control this process thus necessary ensure correct final part limit damage. Lifetime machined depends on surface integrity especially terms microstructure changes residual stresses. The best way those factors study they appear. Thus, it set up experimentation maximum informations during grinding process, with situ measurements after,...

This paper lies in the framework of turning-induced residual stress prediction by presenting an up-dated method based on a two-scale approach. Previous works aimed at building 3D hybrid consisting modelling turning consequences through equivalent thermo-mechanical loadings combining finite element model with experimental tests. The new proposed global strategy keeps same concept but has advantage to define shapes more accurately thanks local 2D orthogonal cutting models. After carefully...

Abstract Inlet distortion can significantly impact turbofan operability. In the present contribution, focus is on vortex ingestion, which a type of that has received less attention in literature for high-bypass-ratio fans civil engines than inlet separation or boundary layer ingestion. Due to unsteady and non-axisymmetric nature inflow, full annulus computations are performed, using an RANS approach with sliding mesh interface between rotor stator. The goal provide detailed analysis...

This paper presents ductile initiation calculations and growth simulations of a surface crack up to pipe wall breakthrough. For validation purpose, one the two BIMET configurations is selected. The EC program has been carried out analyze tearing behavior DMWs through experiments computational analyses. In mock-up, initial defect an external circumferential located close weld-ferritic interface, with depth third thickness. During test, extended aim study simulate growth, compare results...