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This article reports an investigation of the thermal behaviour of the epoxy/LD-slag composites prepared by hand layup method at varied loading of filler from 0 wt. % to 40 wt. %. The main aim of the work is to establish hazardous industrial waste as a filler material for the development of polymer composites. The thermal conductivity of neat epoxy is 0.15 W/m-K and the same improves to 0.292 W/m-K with the addition of 40 wt. % LD-slag. The addition of LD slag appreciably improves the epoxy matrix's thermal stability by increasing its degradation temperature at different levels along with the enhancement in the char residue. The maximum glass transition temperature of 74.74 oC is attained for a filler loading of 20 wt. %, whereas, a negligible reduction is observed at higher filler loading. Further, the material's specific heat capacity also progressed with the inclusion of LD slag and reached 1.115 kJ/kg-oC showing an increment of 57.7 over the neat epoxy resin for a combination of epoxy/40 wt. % LD slag composite. The coefficient of thermal expansion gainfully declines with filler loading and decreases by 14.18 % for 40 wt.% of LD slag. The minimum coefficient of thermal expansion value registered is 59.3 × 10-6/oC. [ABSTRACT FROM AUTHOR]

The current study aims to examine the influence of surface‐modified micro‐sized walnut shell particulates (WSP) with an aqueous solution of sodium hydroxide (NaOH) on epoxy composites. For that, epoxy/WSP composites are prepared by varying the WSP content up to 20 wt%. In this investigation, the physical properties (surface morphology, density, voids percentage, water uptake), mechanical properties (tensile, flexural, compressive, hardness), and sliding wear behavior of the composites are reported. From the micrographs, it is clear that WSP established good adhesion with the epoxy matrix. Further, it is found that the density, void content, water intake capacity, compressive strength, and hardness increase with WSP loading. Against that, the tensile and flexural strength is somewhat reduced at higher filler loading. Sliding wear tests are performed as per L25 Taguchi's orthogonal array. From the analysis, it is observed that WSP content is the most significant factor and sliding distance is the least significant factor for minimizing the wear rate. For analyzing the sliding wear performance under varied conditions, a prediction model is proposed using an artificial neural network to forecast the sliding wear rate of epoxy/WSP composites over a wide range of experimental domains. [ABSTRACT FROM AUTHOR]

Linz‐Donawintz (LD) slag is a solid waste produced during the basic oxygen furnace process of steel making and is more often disposed of on nearby land causing a disturbance in vegetation and human health. Hence, judicial management of LD slag is a need for an hour. For this purpose, the usability of LD slags as a reinforcement material in epoxy composites was investigated in the present work. In this investigation, the physical properties (density, void content, water absorption rate), mechanical properties (tensile properties, flexural properties, compressive strength, hardness), and tribological properties (sliding wear behavior) are reported. From the experimental investigation, it is found that the density, void content, and water intake capacity increase with LD slag loading. The maximum voids present in the composite is 1.92% for epoxy/40 wt. % LD slag composite. Similarly, maximum water uptake of only 0.6% is observed for composite with maximum filler content and for maximum immersion time. Further, it is observed that the strength of composite under tensile and flexural loading was compromised slightly. At 40 wt. % of LD slag, the measured tensile and flexural strength are 20.8 MPa and 28.78 MPa respectively. The strength of composites under compressive loading increases with filler content and reaches a maximum of 108 MPa for epoxy/40 wt. % LD slag composite. The high hardness of filler assists in increasing the hardness of the composites. The hardness of neat epoxy is Shore‐D number 75 which increases to Shore‐D number 84. With increased hardness, ultimately the specific wear rate under dry sliding conditions reduces. Taguchi's L25 orthogonal array having four factors, each at five different levels is implemented to conduct the sliding wear tests. A forecast model is built on an artificial neural network (ANN) which successfully envisages the sliding wear performance of the composite under investigation inside and outside the experimental domain. [ABSTRACT FROM AUTHOR]

Kota stone dust (KSD) and fly ash (FA) are the wastes generated from the construction industry and thermal power plant, respectively. In the present work, a novel hybrid composite is developed to utilize KSD and FA as reinforcing phases in the epoxy matrix. The hand lay‐up method is adopted for the fabrication of 12 sets of samples. Four sets are prepared with single filler KSD and eight samples are prepared with a hybrid combination of KSD and FA. The prepared samples are undergone physical and mechanical tests. To understand the compatibility between filler‐matrix and visualize the dispersion of fillers in epoxy, micrographs are taken using the scanning electron microscope. The density and void contents of the material increases with an increase in filler content. The maximum water absorption measured is 0.96% for the combination of epoxy with 40 wt% KSD and 10 wt% FA. From mechanical testing, maximum tensile strength and flexural strength obtained is 34.4 MPa and 65.4 MPa, respectively, for a combination of epoxy with 20 wt% KSD and 5 wt% FA. Compressive strength and hardness increase with either of the content of the filler and reaches 116.28 MPa and 104 Shore D number, respectively, with 40 wt% KSD and 10 wt% FA. From experimentation, it was found that mechanical properties of the hybrid composites are better as compared to that of single filler composites though physical properties are slightly compromised by hybridization of fillers. [ABSTRACT FROM AUTHOR]