Khairel Rafezi Ahmad
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Preferred name
Khairel Rafezi Ahmad
Official Name
Ahmad, Khairel Rafezi
Alternative Name
Ahmad, Khairel R.
Ahmad, K. R.
Rafezi Ahmad, Khairel
Ahmad, Khairel Rafiez
Ahmad, Khairul R.
Khairel, R. A.
Rafezi, Khairel
Ahmad, Khairel Refazie
Ahmad, Khaireel Rafezi
Main Affiliation
Scopus Author ID
43260917000
Researcher ID
AAK-8057-2020

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Publication

Metallurgist's pocket book

2011 , Kamarudin Hussin , Mohd Ichwan Nasution , Shamsul Baharin Jamaludin , Che Mohd Ruzaidi Ghazali , Khairel Rafezi Ahmad , Mohd Fitri M. W.

Metallurgist's Pocket Book is a handy reference book that can be used by undergraduate students of materials engineering and metallurgy, as well as diploma students of metallurgy. This book contains descriptions of data elements, and characterization of chemical elements, such as melting point, and boiling point, and this book also provides information on the physical and mechanical properties of metals and alloys.

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Recycled Incineration Bottom Ash and Metakaolin as Sustainable Materials for Cement Replacement in Cementitious Composites

2023-01-01 , Roshazita Che Amat , Syakirah Afiza Mohammed , Norlia Mohamad Ibrahim , Nur Liza Rahim , Khairel Rafezi Ahmad , Raischi M.

Study was related to the influence of the concrete properties by using different percentages of metakaolin and fixed percent of incineration bottom ash to partially replace the cement. Cement is a well-known building material and used for the construction in the world. Moreover, the used of metakaolin (MK) and incineration bottom ash (IBA) in this research would give significance to our environment as it can reduce the usage of cement in concrete. By using bottom ash, it could reduce the land filling space. The X-Ray Fluorescence (XRF) test was used to determine the chemical composition of IBA and MK. Four series of concrete have been examined, including control, IBA and MK were used as partial replacement for cement at 10%IBA + 10%MK, 10%IBA + 15%MK and 10%IBA + 20%MK of concrete mixes by volume. The curing period for the samples is 7 days and 28 days. To determine the properties of concrete, the tests such as slump test, density test, water absorption test, pulse velocity test, rebound hammer test and compression test were performed. The results proved that the strength development of 10%IBA + 10%MK concrete sample shows the highest compressive strength after 28 days of curing.

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Mesh refinement for cortical and trabecular bone finite element modeling: A review

2020-12-22 , Mohd Zain, Noor Alia , Ruslizam Daud , Nur Saifullah Kamarrudin , Khairel Rafezi Ahmad , Nurul Huda Abdul Aziz

For centuries, the finite element (FE) method has been extensively used to predict the fracture performance and various method has been implemented to yield accurate results especially in healthcare industries. Bone fracture has been a critical problem since it interrupts the strength and structure of human bone. Thus, this problem will lead to bone malfunction and cause excess bleeding of surround tissues. Human bone consists of cortical and trabecular bone which serve a different amount of load sustainability before the fracture occurred. One of the most vital problems arise is the inaccuracy of the stress intensity factor related to the bone fracture. Recent studies have proven that with the implementation of appropriate meshing element produce higher accuracy results especially with the implementation of mesh refinement in the finite element model. The singularity elements suggested by Barsoum (1976) has proven that the quarter-point triangular elements give highly accurate results. Several methods for stress intensity factor calculation has been implemented by various past researchers. Among all the methods used, J-integral has proven to be the most accurate method compared to the others.The first section in your paper.

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Effects of metakoalin on municipal solid waste incineration (Mswi) bottom ash-cement composite

2020-01-01 , Roshazita Che Amat , Khairul Nizar Ismail , Khairel Rafezi Ahmad , Norlia Mohamad Ibrahim

Municipal solid waste incinerators (MSWI) produce by products which can be classified as bottom and fly ashes. The bottom ash (BA) accounts for 85-90% of solid product resulting from municipal solid waste combustion. The objective of this study was to assess the feasibility of municipal solid waste incineration bottom ash as a supplementary cementations material for the preparation of blended cement. The used of bottom ash as a research material is because of substances contained in bottom ash which is almost same with cement. X-Ray Fluorescence (XRF) spectroscopy analysis was used to determine chemical compositions of the BA and metakoalin (MK) used in this study. Five series of concrete mix design had been examined which contained different percentage of bottom ash and metakaolin as partial replacement for cement in concrete mixes by volume. A few test such as workability, water absorption, and compression test were carried out to investigate properties of grade 20 concrete incorporating bottom ash and metakaolin. The concrete cubes were tested at age of 7 and 28 days to study the development its compressive strength. Concrete mix design with 10% BA and 10% MK shows the highest strength of 32.9 MPa and surpassed strength 20 MPa. Bottom ash was found to have some reactivity, but without greatly affecting the hydration process of Ordinary Portland cement (OPC) at 10% replacement with 10% metakaolin is required to be used in the production of concrete in order to improve strength.

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Pengenalan kepada ujian bahan tanpa musnah

2013 , Mohd Arif Anuar Mohd Salleh , Khairel Rafezi Ahmad , Dewi Suriyani Che Halin , Siti Hawa Mohamed Salleh , Muhammad Hafiz Zan @ Hazizi

Pengenalan Kepada Ujian Bahan Tanpa Musnah merupakan sebuah buku yang membincangkan beberapa perkara asas yang penting dalam ujian tanpa musnah. Ia meliputi kebanyakan kaedah ujian tanpa musnah yang sering digunakan di industri. Buku ini memberi penerangan dalam ujian bahan tanpa musnah yang sering digunakan dalam industri bagi memeriksa kecacatan atau ketidaksempurnaan sesuatu bahan tanpa merosakkan atau memusnahkan bahan yang diperiksa. Keseluruhan kandungan buku ini merangkumi perbincangan dari aspek teori serta konsep pengujian, kaedah pengujian, dan aplikasi ujian dalam industri.

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