Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : fracture toughness


Flexural and Impact Properties of Epoxy Composites Reinforced with Peanut Shell Particles

Hwazen Fadhil

Engineering and Technology Journal, 2020, Volume 38, Issue 7, Pages 1026-1033
DOI: /10.30684/etj.v38i7A.584

Natural materials have been extensively used as reinforcements in polymer matrices instead of non-degradable synthetic reinforcement such as carbon, glass or aramid. The use is because of their low density, good mechanical properties, availability, and biodegradability. Peanut shell is one such natural waste filler used, and it contains cellulose, hemicellulose, and lignin. Natural fiber/particle sources are not only strong and lightweight but are relatively very cheap. This paper offers the comparison of the flexural, and impact energy test properties of the peanut shell reinforced with the epoxy resin matrix. Peanut shells add into the epoxy resin matrix with various weight fractions (2%, 4%, 6%, and 8%) and have been fabricated by hand lay-up procedure. Flexural strength and flexural modulus changed from (140MPa) to (160 MPa), and from (2 GPa) to (7.79 GPa) respectively, impact strength, and fracture toughness changed from (2.5 KJ/m2) to (7 KJ/m2), and from (2.23 MPa.m1/2) to (7.07 MPa.m1/2), respectively as a function of the particle weight fraction. The highest flexural strength and modulus obtained samples (reinforced 4% wt. peanut shell), while samples (reinforced +8% wt. peanut shell) provided the highest impact strength and fracture toughness.

Synthesis of B4C/YTZP Composite Powder and Studying Effect of its Addition on Mechanical Properties of B4C

Fadhil A. Chyad; Mohammed H. AL-Taie; Hussein AlaaJaber

Engineering and Technology Journal, 2014, Volume 32, Issue 5, Pages 1158-1170

In this research B4C powder have been coated with yttria stabilized tetragonal zirconia polycrystalline (YTZP) (ZrO2 – 6wt% Y2O3) by using sol-gel method in order to obtain on composite powder (B4C core/ YTZP shell, 1/1 wt%). Zirconium oxychloride (ZrOCl2.8H2O) and yttrium nitrate (Y(NO3)3.6H2O) were used as the precursors for synthesis of the YTZP compound. The coated B4C powder was then used as additive powder to B4C. It was mixed with different percentages for making ceramic–ceramic composite samples. The YTZP weight percentages added to the B4C were in the range (0–12.5) wt%. The samples sintered by using spark plasma sintering technique at 1800 and 1900°C for 5 min. Density and mechanical properties (Vickers microhardness, fracturetoughness and fracturestrength) for the sintered samples were measured. The results show that the best YTZP additions to the B4C that have good mechanical properties were ranged 5 – 7.5 wt%.

A Model for The Prediction of Fracture Toughness Using Neural Network

Aseel abdulbaky; Dhafer Al-Fattal; Harry Bhadeshia; Talal Abdul Jabbar

Engineering and Technology Journal, 2012, Volume 30, Issue 5, Pages 868-885

The purpose of this research programme is to develop quantitative models for the prediction of mechanical properties (fracture toughness) using experimental data collected from the literature, together with a powerful computational technique known as neural network. Creating a truly general model requires a combination of available data and metallurgical knowledge. This model is proposed for martensitic and ordinary bainitic steels in addition to the more recent class of non-structural super-bainitic steels. Super-bainitic steels are
attractive for many applications such as armour. The model of fracture toughness, based on chemical composition, heat treatment an
d mechanical properties is proposed. The predictions of fracture toughness are generally acceptable but the uncertainties
are high and more input data need to be collected for super-bainitic steels when available in the future to improve the predictions of this model.

The Effect of Waste Ceramic Materials ( Iraqi Stones Dust Powders ) on The Mechanical Properties of Epoxy Resin

Fadhil A.Chyad

Engineering and Technology Journal, 2011, Volume 29, Issue 16, Pages 3302-3312

Using waste materials, which have a high pollution on the environment, as an improvement to the properties of a weaken material such epoxy resin become a good achievement. Iraqi stones dust powders have been used to improve the mechanical properties of epoxy resin. Impact strength and fracture toughness from impact test, Young`s modulus from tensile test, Shore hardness, fracture toughness and thermal
conductivity have been investigated. The percentages of the ceramic powders have affected all the above properties and increased the values of them about twice. The highest values were at 12% and then decreased. Also the particle size of this powders has affected these properties, where the lowest particle size (25ìm) has the best values.

Study Some Physical and Mechanical Properties of Ceramic – Ceramic Fibers Composite

Fadhil Attiya Chyad

Engineering and Technology Journal, 2011, Volume 29, Issue 9, Pages 1631-1640

Zirconia fibers have been prepared by convertional method using cotton threads
impregrated in zirconium oxychloride solution ( ZrOCl2. 8H2O ). X-ray
diffraction shows the crystallinity of zirconia and optical microscopy shows the
fibers fabrication. Differnet percentage ( 2 ,4 ,8 , 10 and 12 ) of prepared zirconia
fibers mixed with ZnO powder.
All the specmen sintered at 1250 °C for 2hrs. Physical properties (density and
volume shrinkage) were measured and Mechanicl properties (Vicker ̉s
hardness,fracture strength and fracture toughness by indentation method ) were
calculated, 10% of fiber content has the maximum values for these properties for
the composite.