【開催報告】2026.10.13 -第200回構材ゼミ- Dr. Anand K Kanjarla (Indian Institute of Technology Madras)
講演後の集合写真
Dr. Anand K Kanjarla (後列左から6番目)
- 日時
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2026年10月13日（火曜日）10：30-11:30
- 場所
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NIMS千現地区 先進構造材料研究棟5階カンファレンスルーム
- 講演題目
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Crystal plasticity-based modelling of deformation in metallic materials
- 講演者
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Dr. Anand K Kanjarla
Indian Institute of Technology Madras
kanjarla@iitm.ac.in, home.iitm.ac.in/kanjarla
Abstract:
Mechanical response of materials measured at the macroscopic scale is a manifestation of physical phenomena occurring at multiple lower length scales. Crystal plasticity-based constitutive models at the continuum microstructural scale have the advantage of easy scale transition. They can be easily embedded in engineering-scale finite element codes. At the same time, they provide the flexibility to incorporate the homogenised behaviour of discrete processes happening at lower length scales.
In the first part of this talk, following a brief overview of crystal plasticity, I present our recent work on understanding the room-temperature low-cycle fatigue behaviour of Inconel 718 with two different initial microstructures: double-aged (aged) and solution-annealed (SA), with and without γ'' precipitates, respectively. Analysis of hysteresis loops using the Cottrell stress decomposition method indicates that, although the backstress is nearly the same under both conditions, the effective stress is significantly higher in the aged condition. A detailed microstructural analysis, along with a modelling framework, is utilised to rationalise the relative contributions of the physical mechanisms responsible for backstress and the effective stress during the cyclic loading.
In the second part of the talk, I present some recent efforts in modelling the effects of hydrogen in materials. First, I will present an atomistically informed crystal plasticity study to show that the location of hydrogen in the vicinity of a dislocation affects the yield stress of 𝛼𝛼-Fe. Second, I will present our work on how phase morphology and martensite fraction affect hydrogen permeation in dual-phase steels, using a coupled diffusion-mechanics finite-element framework.