جستجوی مقالات مرتبط با کلیدواژه « واکس » در نشریات گروه « مواد و متالورژی »

In this study, some granulated and pressable formulations based on coating of pentaerythritol tetranitrate (PETN) explosives with high impact polystyrene polymer (HIPS), Viton fluoroelestomer and paraffin wax were developed. Thereafter, mechanical strength of pressed formulations and transition temperature of binders were evaluated using uniaxial compressive strength test and differential scanning calorimetric (DSC) method, respectively. Also, the effect of PETN particle size distribution on compressibility, mechanical strength, density and particle size of pressed samples based on HIPS binder were statistically studied and optimized using mixture design of experiments by Minitab software. In the optimized experimental conditions, the compressive strength and elastic modulus for PETN/HIPS mixture at ambient temperature and at the concentration of 4.0 wt.% of the binder, were 15.0 and 91.1 MPa, which is better than formulations based on expensive Viton polymer and paraffine wax. By using HIPS binder, increasing the amount of PETN particle size <150 μm, mechanical strength of pressed samples decrease, and also particle size distribution in the range of 150-300 μm , leads to production of better formulations.

In this study, self-stratified metallic surface coating based on polyurethane resin consisting of single-layer polymer acrylic with high gloss, without the use of clear coat, with the aim of covering industrial parts, home appliances and even car body repair was designed and formulated. The purpose of the work was to reduce the amount of consumables, work error and coverage time compared to the conventional and traditional coating (two layers of coating consisting of metallic base coat and clear coat). To design the experiments (DOE), the Taguchi method was used to optimize the type and amount of the main raw materials, including polyol acrylic resin type, cellulose acetate butyrate and wax. Various tests such as adhesion, gloss, hardness, abrasion salt fog and immersion were performed on the formulated coatings. The results showed, for example, an optimal adhesion rate of (5B), a gloss about 89%, mottling level of 51, and hardness of 210 seconds. Also, no sedimentation was observed in the liquid state and the results of moisture resistance and water immersion tests were acceptable based on standard criteria, compared to conventional double-layered samples.

D-2 Composition is used as a desensitizing agent for explosive material.It is a homogenouse mixture formed of nitrocellulose, lecithin and wax, with specific characteristics. Usage of this composition in explosive mixtures will dilute and coat surface of granules of explosives which results in increasing stability and reducing sensitivity of explosives. In this paper, at the first, the desnsitizing mchanisms of explosives, has been discussed, latter the effect and properties of D-2 millitary wax has been described.Finally the properties of raw materials and the production of military wax have been studied,also the factors effecting quality of mass production have been mentioned.