© 100 Journal homepage: http://twasp.info/journal/home Research Effect of Tungsten Content on Corrosion Resistance and Hardness of Aluminum by Electro-less Coating Muhammad Azeem ullah 1 , Salah Ud Din 1 , Ayesha Azeem 1 , Faisal Nazeer 2 , Abdul Malik 2 , Muhammad Nouman Khan 3 , Muhammad Sajid 4* 1 State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, People’s Republic of China 2 School of Materials Science and Engineering, Beijing Institute of Technology,Beijing 100081, China 3 School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, China. 4 Beijing Key Laboratory of Construction-Tailorable Advanced Functional Materials and Green Applications, School of Materials, Beijing Institute of Technology, Beijing, China * Corresponding author Accepted:12 August, 2019 ;Online: 19 August, 2019 DOI : https://doi.org/10.5281/zenodo.3371786 Introduction: Abstract:Nickle-Tungsten-Phosphorous (Ni-W-P) alloy coating was prepared by electro- less nickel plating on pure aluminum sheet. For activation of aluminum surface, pickling and zinc immersion was carried out. Furthermore, reinforcement and reduction of corrosion potential, copper electroplating was inspected before deposition for better adherence. In this present research work focus on the variation of tungsten content in chemical plating bath for constant plating time. Scanning Electron Microscopy (SEM) was used to observe the surface morphology of the samples. Energy Dispersive Spectroscopy (EDS) was used to determine the coating composition and thickness of the coating catalyst. Behavior of hardness was measured by Vickers hardness tester techniques while its porosity have been observed by stereoscope. The medium used for corrosion resistance testing was 0.9% sodium chloride (NaCl) with hydrochloric acid (HCl) giving 4-5 pH. The predominant phase in the coating was nickel along with phosphides of nickel and nodules of tungsten content. Coating showed higher hardness and good corrosion resistance as compared to substrate. With increase in tungsten content, hardness increased and spherical size was decreased. Hence, uniform and thick coating was obtained. Keywords : Aluminum surface;Corrosion potential;Tungsten; Electroplating;Hardness