Corrosion behaviour and surface topography for steel plates used in automotive industry exposed to salty corrosive thermo-accelerated medium

Corrosion resistance is one of the essential criteria in the automotive industry, especially in harsh climates, as it causes severe damage to vehicles. Therefore, the anti-corrosion factor should be a complementary and integral part of other safety standards. An experimental investigation for monitoring and evaluating the corrosion behavior of high strength low carbon steel plates with different surface characteristics and treatments conditions used in the automotive industry exposed to a salty, corrosive thermo-accelerated medium has been introduced in this empirical study. The produced samples are divided into four main groups: welded, unwelded, coated, and uncoated. These samples were exposed to an aggressive chemical medium consisting of salty-aqueous spray with a 5% NaCl concentration at 35°C with speed and pressure. All changes in surface features, including topography, roughness, and corrosion products, were measured and analyzed periodically every 8 hours for 24 hours by scanning electron microscopy, optical microscopy, and CSPM imager surface roughness analysis. The results showed that the coated samples had lower roughness values and lower corrosion products after 24 hours under the salty-aqueous spray test

Flammability action of tires material after adding flame inhibitor

Magnesium hydroxide was used as flame inhibitor to increased flame resistance for tires .Magnesium hydroxide was adding with (5%,10%) weight percents to rubber master batch of tire and then exposed the resulting material to a flame generated from gas torch with (10 mm) exposure distance . Method of measuring the surface temperature opposite to the flame was used to determine the heat transferred through tire material. The results were obtained shows enhanced flame resistance for tire by added magnesium hydroxide and this resistance increased by increasing hydroxide Percentage

A Novel Evaluation Method for Dehydrochlorination of Plasticized Poly(vinyl chloride) Containing Heavy Metal Free Thermal Stabilizing Synergistic Agent

A novel method for determining the level of dehydrochlorination, that is, the conversion of degradation from the conductivity curve of plasticized Poly(vinyl chloride) (PVC) containing heavy metal-free agent, has been used. The novel method was introduced in this article to evaluate the thermal stability of PVC by dehydrochlorination that shows more reproducibility for measured results than the standard method, which depends on the conductivity only. The novel method was used to measure thermal degradation in a new generation of thermal stabilizing heavy metal-free additive added to plasticized PVC, which is Oxydtron (a nanocement additive). Plasticized PVC containing Oxydtron is our new candidate to replace conventional stabilizers or at least increase their efficiency. The primary use of this new material is in the cable grade industry and construction applications. The basic principle of our novel method is based on converting the conductivity data obtained by the conventional or standard method to HCl concentration. The data analysis graph will have two curves instead of the one conductivity curve, representing the conversion and HCl concentration. In this study, a comparison was made between the results of the novel method with the results obtained from the conventional or standard method. In contrast to the standard method, it describes better the process, particularly in the case of PVC compounds. This method's designed computer program shows a good agreement with the discoloration and initial color changes

Heat effected zone in unburned, antimony trioxide containing plasticised PVC

What are the structural changes in the PVC layer located directly under the flame zone which is exposed to high temperatures without burning? We will try to explain in this article what actually happens in this layer, which we called heat affected zone. The layers were tested both with and without antimony trioxide (ATO or Sb2O3) flame retardant additive. Results obtained from Scanning Electron Microscopy (SEM) for the heat affected zone of the samples after Limited Oxygen Index (L.O.I) test and compared with the samples before this test showed that there was a significant decrease in the chlorine content in the PVC structure accompanied by a significant increase in the carbon content. We suppose that this early dehydrochlorination improves the efficiency of Sb2O3

Heavy metal free thermal stabilizing-flame retarding modifier for plasticized poly(vinyl chloride)

Our research aimed to find efficient heavy metal free flame retardant for cable grade plasticized poly(vinyl chloride) comparable to the conventional flame retardants. One of the candidates, is artificial silicate (Oxydtron®) proved to be an efficient flame retardant and surprisingly showed excellent heat stabilizing effect as well. Tests were done on limiting oxygen index (L.O.I.), heat stability by static method and Congo-red, differential scanning calorimetry (DSC). These thermal tests proved the ability of Oxydtron to improve the properties of poly(vinyl chloride) at high temperatures reducing the risks associated with combustion of plasticized poly(vinyl chloride) by increasing its thermal stability, which will lead to open a new horizon in the poly(vinyl chloride) industry. Unfortunately, this excellent material is not available yet in white color because of its coloring impurities

Performance Evaluation of Mixing Mechanism and its Effects on Thermal Behaviour of Plasticised PVC

The effect of mixing by hand and mixing by mechanical mixer on limiting oxygen index ,thermal stability and DSC of plasticised PVC has been studied in this article. LOI Stanton Redcroft FTA flammability unit, Stabilimetr PVC 03, and DSC823e were used for measuring limiting oxygen index and thermal stability of plasticised PVC. The experimental results showed that limiting oxygen index and thermal stability of plasticised PVC mixing by hand higher than mixing by mechanical mixer, because there is an irregular distribution of chlorine, carbon and oxygen elements inside the PVC structure, where there is a conglomeration of these elements at some points in case of mixing by hand and more homogeneous in case on mixing by mechanical mixer, as illustrated by scanning electron microscopy (SEM) images and the energy-dispersive X-ray spectroscopic micro-analyzer (EDS). Therefore, this irregular distribution will give inaccurate results for limiting oxygen index of plasticised PVC

L.O.I. and DSC analyses of antimony trioxide containing plasticised PVC as a function of processing method

The correlation between the processing method and thermal properties of antimony trioxide containing plasticised PVC has been studied in this paper. Two processing methods included rolling and single screw-extrusion were used to produce PVC-ATO samples, and observe the effect of each method on the thermal properties limiting oxygen index (L.O.I) and differential scanning calorimetry (DSC) of the samples. The results obtained from the thermal tests showed that the extrusion method was better than the rolling method for L.O.I and DSC (gelation grade). This is due to the heat will distributed uniformly in the screw-extrusion method, which reduces thermal stresses in the final product