International Journal of Computational Materials Science and Surface Engineering (5 papers in press)

Regular Issues

• Anisotropic electronic and optical behaviour of monolayer SiP for next generation devices  
  by Usha Shukla 
  Abstract: Two dimensional (2D) low symmetry materials have recently emerged as promising platforms for next generation optoelectronic devices due to their intrinsic anisotropic electronic and optical properties. In this work, we present a comprehensive first principles investigation of the anisotropic electronic structure and polarisation sensitive optical response of monolayer silicon phosphide (SiP), a group IV-V layered semiconductor with an orthorhombic crystal structure. The reduced in plane symmetry of SiP gives rise to pronounced direction dependent band dispersion, leading to significant effective mass asymmetry and anisotropic carrier transport along armchair and zigzag directions. Detailed analysis of orbital contributions reveals that hybridised Si-P states dominate near the band edges, governing the anisotropic electronic behaviour. Furthermore, the optical response exhibits strong polarisation dependence, with distinct absorption characteristics and enhanced light matter interaction along specific crystallographic orientations. The study also highlights nonlinear optical behaviour, including polarisation dependent third harmonic generation (THG), confirming the potential of SiP for advanced photonic applications.
  Keywords: monolayer silicon phosphide (SiP); anisotropic electronic properties; polarisation dependent optical response; low symmetry 2D materials; polarisation sensitive photodetectors; nonlinear optics (THG).
  DOI: 10.1504/IJCMSSE.2027.10079247
   
  
• Investigation through numerical simulation and experimental validation of square bar extrusion of Al-Mg-Si alloy  
  by Surendra Kumar Ghadai, Sambit Kumar Mohapatra, B. Surekha, Basanta Kumar Nanda 
  Abstract: In the present study, the flow characteristics during the extrusion of an Al-Mg-Si alloy were investigated using a computational numerical simulation approach. The novelty of this work lies in incorporating the influence of velocity relative difference (VRD) and punch profile on material flow characteristics and maximum load requirement for extrusion. Out of all the variable parameters, friction had a strong influence on VRD, markedly altering the extrudates flow pattern. To assess the influence of punch geometry on flow characteristics, simulations were conducted using flat, inner-cone, and conical punches. The flow grid pattern exhibited corresponding variations, highlighting distinct deformation characteristics. As maximum plastic deformation occurs at the billet boundaries, the micro-hardness of the experimented specimen exhibited a gradient, increasing from the core toward the outer surface. Furthermore, due to the inverse relationship between redundant work and die length, a shorter die is more effective under high friction conditions.
  Keywords: DEFORM-3D; extrusion; metal forming; finite element simulation; aluminium alloy; VRD; velocity relative difference.
  DOI: 10.1504/IJCMSSE.2027.10080306
   
  
• Next-generation composite analysis with a computational framework for tensile strength prediction  
  by Wenming Zhang 
  Abstract: Accurately predicting the tensile strength of composite materials remains difficult due to their complex, nonlinear, and multiscale behaviour. This study presents an optimised computational framework that combines the Radial Basis Function model, the Gaussian process regression (GBR) model, and the light gradient boosting regression (LGBR) model with the Rider Optimisation Algorithm (ROA) to enhance predictive accuracy. The hybrid approaches were evaluated using common statistical error metrics. The model that paired LGBR with the ROA achieved the best performance, with a coefficient of determination of 0.976 and a root mean squared error of 106.69 across the entire dataset. The significance of this work lies in uniting advanced machine learning models with a nature-inspired optimisation strategy to offer a more reliable method for predicting the tensile strength of composite materials.
  Keywords: composite materials; tensile strength projection; regression schemes; hybrid schemes; ML; machine learning; material science.
  DOI: 10.1504/IJCMSSE.2027.10080970
   
  
• Tribological performance of hydrodynamic textured thrust pad bearing: a numerical and experimental investigation  
  by Pruthwiraj Sahu, Suraj Kumar Behera, Smitirupa Pradhan, Asit Behera 
  Abstract: The surface texturing of mating solids plays a crucial role in controlling tribological behaviour at the interface. For a constant gap, textured surfaces can significantly enhance the load-carrying capacity compared to plain thrust pad bearings. In this study, an axial thrust pad bearing is modelled to examine the influence of texture height and aspect ratio on lubrication performance. A numerical analysis is conducted to evaluate the effects of hemispherical, semi-elliptical, cylindrical, and square-shaped textures on parallel thrust pad bearings. Pressure distribution and load carrying capacity were predicted using finite difference method and to complement the analysis, thrust pads with three different texture heights are fabricated on mild steel surfaces using a cost-effective chemical etching process. The manufactured pads are tested in bearing setup under varying load and speed to assess their tribological performance. Results indicate that cylindrical textures with higher texture height ratios (THRs) and lower aspect ratios deliver superior bearing performance.
  Keywords: hydrodynamic; thrust pad bearing; chemical etching; surface texturing; tribological performance; film thickness; frictional torque.
  DOI: 10.1504/IJCMSSE.2027.10081753
   
  
• Formaldehyde barrier properties and thermal ageing properties of nano-titanium dioxide/resin composites under high temperature environment  
  by Li Lyu, Binxu Xie, Shuangshuang Wang 
  Abstract: In response to the thermal aging degradation and formaldehyde release issues of resin based composite materials under high temperature environments, this paper uses silane coupling agents to modify the surface of rutile type nano TiO2. Firstly, this paper introduces it into the high-density polyethylene (HDPE) and polyester TGIC ((Triglycidyl isocyanurate) resin system through melt blending technology, and optimises the process parameters to achieve uniform dispersion of nanoparticles. Finally, the system evaluates the performance of composite materials under high-temperature accelerated aging and formaldehyde catalytic degradation conditions. The results showed that the formaldehyde degradation rate of 1.5 wt% modified TiO2/HDPE reached 95.6% under visible light for 48 h, which was 39.1% higher than the unmodified group. Modified TiO2 suppresses the thermal motion of molecular chains by forming Ti-O-Si covalent bonds, increasing the initial thermal decomposition temperature of HDPE by 40?C.
  Keywords: nano titanium dioxide; surface modification; formaldehyde barrier performance; thermal ageing stability; percolation network.
  DOI: 10.1504/IJCMSSE.2027.10081846