Finite element modeling of residual stress profile patterns in hard turning

Hard turning, i.e., turning hardened steels, may produce the unique “hook” shaped residual stress (RS) profile characterized by surface compressive RS and subsurface maximum compressive RS. However, the formation mechanism of the unique RS profile is not yet known. In this study, a novel hybrid finite element modeling approach based on thermal-mechanical coupling and internal state variable plasticity model has been developed to predict the unique RS profile patterns by hard turning AISI 52100 steel (62 HRc). The most important controlling factor for the unique characteristics of residual stress profiles has been identified. The transition of maximum residual stress at the surface to the subsurface has been recovered by controlling the plowed depth. The predicted characteristics of residual stress profiles favorably agree with the measured ones. In addition, friction coefficient only affects the magnitude of surface residual stress but not the basic shape of residual stress profiles.

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A New Finite Element Approach Without Chip Formation to Predict Residual Stress Profile Patterns in Metal Cutting

ASME 2009 International Manufacturing Science and Engineering Conference, Volume 1 ◽

10.1115/msec2009-84236 ◽

2009 ◽

Cited By ~ 1

Author(s):

S. Anurag ◽

Y. B. Guo ◽

Z. Q. Liu

Keyword(s):

Residual Stress ◽

Finite Element ◽

Hard Turning ◽

Metal Cutting ◽

Cutting Speed ◽

Stress Profile ◽

Residual Stress Profile ◽

Stress Prediction ◽

Element Approach ◽

Stress Profiles

Residual stress prediction in hard turning has been recognized as one of the most important and challenging tasks. A hybrid finite element predictive model has been developed with the concept of plowed depth to predict residual stress profiles in hard turning. With the thermo-mechanical work material properties, residual stress has been predicted by simulating the dynamic turning process followed by a quasi-static stress relaxation process. The residual stress profiles were predicted for a series of plowed depths potentially encountered in machining. The predicted residual stress profiles agree with the experimental one in general. A transition of residual stress profile has been recovered at the critical plowed depth. In addition, the effects of cutting speed, friction coefficient and inelastic heat coefficient on residual stress profiles have also been studied and explained.

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Finite Element Modeling of Residual Stress at Joint Interface of Titanium Alloy and 17-4PH Stainless Steel

Metals ◽

10.3390/met11040629 ◽

2021 ◽

Vol 11 (4) ◽

pp. 629

Author(s):

Nana Kwabena Adomako ◽

Sung Hoon Kim ◽

Ji Hong Yoon ◽

Se-Hwan Lee ◽

Jeoung Han Kim

Keyword(s):

Residual Stress ◽

Finite Element ◽

Stainless Steel ◽

Finite Element Modeling ◽

Equivalent Stress ◽

Stress Gradient ◽

Joint Interface ◽

Element Modeling ◽

Actual Experiment ◽

Maximum Equivalent Stress

Residual stress is a crucial element in determining the integrity of parts and lifetime of additively manufactured structures. In stainless steel and Ti-6Al-4V fabricated joints, residual stress causes cracking and delamination of the brittle intermetallic joint interface. Knowledge of the degree of residual stress at the joint interface is, therefore, important; however, the available information is limited owing to the joint’s brittle nature and its high failure susceptibility. In this study, the residual stress distribution during the deposition of 17-4PH stainless steel on Ti-6Al-4V alloy was predicted using Simufact additive software based on the finite element modeling technique. A sharp stress gradient was revealed at the joint interface, with compressive stress on the Ti-6Al-4V side and tensile stress on the 17-4PH side. This distribution is attributed to the large difference in the coefficients of thermal expansion of the two metals. The 17-4PH side exhibited maximum equivalent stress of 500 MPa, which was twice that of the Ti-6Al-4V side (240 MPa). This showed good correlation with the thermal residual stress calculations of the alloys. The thermal history predicted via simulation at the joint interface was within the temperature range of 368–477 °C and was highly congruent with that obtained in the actual experiment, approximately 300–450 °C. In the actual experiment, joint delamination occurred, ascribable to the residual stress accumulation and multiple additive manufacturing (AM) thermal cycles on the brittle FeTi and Fe2Ti intermetallic joint interface. The build deflected to the side at an angle of 0.708° after the simulation. This study could serve as a valid reference for engineers to understand the residual stress development in 17-4PH and Ti-6Al-4V joints fabricated with AM.

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Finite element modeling of acousto-mechanical coupling in the cat middle ear

The Journal of the Acoustical Society of America ◽

10.1121/1.2912438 ◽

2008 ◽

Vol 124 (1) ◽

pp. 348-362 ◽

Cited By ~ 33

Author(s):

James P. Tuck-Lee ◽

Peter M. Pinsky ◽

Charles R. Steele ◽

Sunil Puria

Keyword(s):

Finite Element ◽

Finite Element Modeling ◽

Middle Ear ◽

Mechanical Coupling ◽

Element Modeling

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Study of Effect of Repetition Rate on Laser Shock Peening Using Finite Element Modeling

Volume 2: Manufacturing Processes; Manufacturing Systems; Nano/Micro/Meso Manufacturing; Quality and Reliability ◽

10.1115/msec2020-8485 ◽

2020 ◽

Author(s):

Sai Kosaraju ◽

Xin Zhao

Keyword(s):

Shock Wave ◽

Residual Stress ◽

Finite Element ◽

Shock Waves ◽

Repetition Rate ◽

High Repetition Rate ◽

Stress Profile ◽

Surface Residual Stress ◽

Residual Stress Profile ◽

High Repetition

Abstract A two-dimensional finite element model is developed to simulate the interaction between metal samples and laser-induced shock waves. Multiple laser impacts are applied at each location to increase plastically affected depth and compressive stress. The in-depth and surface residual stress profiles are analyzed at various repetition rates and spot sizes. It is found that the residual stress is not sensitive to repetition rate until it reaches a very high level. At extremely high repetition rate (100 MHz), the delay between two shock waves is even shorter than their duration, and there will be shock wave superposition. It is revealed that the interaction of metal with shock wave is significantly different, leading to a different residual stress profile. Stronger residual stress with deeper distribution will be obtained comparing with lower repetition rate cases. The effect of repetition rate at different spot sizes is also studied. It is found that with larger laser spot, the peak compressive residual stress decreases but the distribution is deeper at extremely high repetition rates.

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