S Kamal

The below code written in the MATLAB® can be used for generating the Gyroid structure.  %% Program clc; clear all; n1 = 2;  % Number of cells in x Direction n2 = 2;  % Number of cells in y Direction n3 = 2; % Number of cells in z Direction   a=2*n1*pi; % x direction parameters b=2*n2*pi; % y direction parameters g=2*n3*pi;  % z direction parameters   s=0.01;   [x,y,z]=meshgrid(-0.5:s:0.5,-0.5:s:0.5,-0.5:s:0.5);   % Gyroid Formula u = (sin(a.*x).* cos(b.*y) + sin(b.*y).* cos(g.*z) + sin(g.*z).* cos(a.*x));   % Level Set equation c =0.7; Ts= -(u+c).*(u-c);    % Sheet based Gyroid Tsk= u + c;        % Skeletal based Gyroid Isosurface(x,y,z,Ts,0); Isocaps(x,y,z,Ts,0); %% Program Ends If very less knowledge about coding, then the below software can be used for generating Gyroid and other lattice structures. Using Lattice_Karak  helps in designing v...

Lattice structures are getting lots of momentum in various fields due to their eccentric properties [1] . It is very important to have easy method to design these lattice structures. Lattice_Karak [2] helps in getting the work done. It is free software with UI made for students and researchers. Using Lattice_Karak  helps in designing various TPMS structures, export them into stl file for further processing like 3D printing and Finite Element analysis.   Lattice_Karak can be downloaded using the below link. https://drive.google.com/file/d/1WWL-UbPzErFCFVFJqw1as9w0M61aMxB4/view?usp=sharing   Videos on how to further use lattice_karak. https://youtu.be/CuHQwsxPa3I   https://sites.google.com/iith.ac.in/lattice-karak/home   Suggested materials for understanding more about TPMS: 1)      https://doi.org/10.1016/j.addma.2017.12.006 2)      https://doi.org/10.1016/j.matdes.2017.03.018 3)      https://doi.org/10...

  Below is the MATLAB program for the generation of TPMS lattices. clc; clear all; a=pi;      %d     No of unit cells s=pi/10;  [x,y,z]=meshgrid(-a:s:a,-a:s:a,-a:s:a);   u = (cos(x).*cos(y).*cos(z))- (sin(x).*sin(y).*sin(z)); ; % d TPMS formula isosurface (x, y, z, u,0);

 Effect of Shielding Gas on parts manufactured by WAAM. Wire arc additive manufacturing (WAAM) is a fusion manufacturing process in which the heat energy of an electric arc is employed for melting the electrodes and depositing material layers for wall formation or for simultaneously cladding two materials in order to form a composite structure. Effect of shielding gas  Argon  Low arc temperature and low thermal conductivity  Nitrogen  Free burning arcs are unstable N2 being a diatomic molecule, first will dissociate into its atoms and only then ionize. So the formation of the ionization column is harder in N2     ACM (80% Ar + 20% CO2)   The best shielding gas compared to the above gases References: Chaturvedi, M.; Scutelnicu, E.; Rusu, C.C.; Mistodie, L.R.; Mihailescu, D.; Subbiah, A.V. Wire Arc Additive Manufacturing: Review on Recent Findings and Challenges in Industrial Applications and Materials Characterization. Metals 2021, 11, 939. ht...

  The below report gives detailed information on the preparation of Bioink. press the below link to access it Click here https://docs.google.com/document/d/1tRARvLOMNCCgVrJRtgExFnajDo-ZFRaM/edit?usp=sharing&ouid=116321863313590654612&rtpof=true&sd=true Image source:  Gopinathan J, Noh I. Recent trends in bioinks for 3D printing. Biomater Res. 2018 Apr 6;22:11. doi: 10.1186/s40824-018-0122-1. PMID: 29636985; PMCID: PMC5889544.   Biofabrication lab @IITH

The below report gives detailed information on the preparation of Hydrogel. press the below link to access it Click here https://docs.google.com/document/d/1Tmflgdsj4Gpyhp9PlwN96Tk6bUeCU3Lx/edit?usp=sharing&ouid=116321863313590654612&rtpof=true&sd=true Image source:    Pati, F., Jang, J., Ha, DH. et al. Printing three-dimensional tissue analogues with decellularized extracellular matrix bioink. Nat Commun 5, 3935 (2014). https://doi.org/10.1038/ncomms4935     Biofabrication lab @IITH

       The below report gives a detailed report on printing a prosthetic socket. Press the below link to access it    Click here https://docs.google.com/document/d/1PrcXwssPLtQHWdPk6Z9SVTCNRkbn68xk/edit?usp=sharing&ouid=116321863313590654612&rtpof=true&sd=true  Biofabrication lab @IITH       

  There are a number of key features that are common to any extrusion-based system: – Loading of material – Liquification of the material – Application of pressure to move the material through the nozzle – Extrusion – Plotting according to a predefined path and in a controlled manner – Bonding of the material to itself or secondary build materials to form a coherent solid structure – Inclusion of support structures to enable complex geometrical features.

  List of precipitation hardened alloys and shape of precipitate S. No Alloy Precipitate Shape Reason for the shape Reference 1 Inconel 718 Delta phase Plate To reduce strain energy (caused due to lattice miss fit, the b direction length is different from the matrix) it grows in plate like structure because Mahadevan, S., Nalawade, S., Singh, J. B., Verma, A., Paul, B., & Ramaswamy, K. (2010). Evolution of δ phase microstructure in alloy 718. 7th International Symposium on Superalloy 718 and Derivatives 2010 , 2 , 737–750. https://doi.org/10.1002/9781118495223.ch57   2 Al–43%Zn-2%Cu Zn Ellipsoidal Due coherent interface between Zn (0002) and Al (111) Han, S. Z., Choi, E. A., Park, H. W., Lim, S. H., Lee, J., Ahn, J. H., Hwang, N. M., & Kim, K. (2017). Simultaneous increase in streng...

  Free energy compositional diagram for eutectic system                                             Figure 1: Eutectic Phase diagram at atmospheric pressure.                                             Figure 2: Free energy compositional diagram at Temperature T1.                                                 Figure 3: Free energy compositional diagram at Temperature T2                                     Figure 4: Free energy compositional diagram at Temperature T3.                         ...

 

     Role of Microstructure on Optical Properties                                               Key words- Anti reflective surface (ARS), Bioinspired, Optical properties. I. INTRODUCTION The Optical properties of a material can be defined as how the material interacts with light but strictly speaking it is the response of a material to the electromagnetic radiation. The major optical properties are Refraction, Polarization, Reflection, Absorption etc.      With the advent of the silicon age the demand for the materials which shows excellent optical properties are needed which helps in increasing the efficiency of data transfer (optical fibers), Energy production (Solar cells), etc. This paper explains the recent development in the materials microstructure leading to a humongous changes in optical properties, it also discuss how this micr...