Steel substrate

Tf > 13% has been achieved for a three-stacked cell on a stainless steel substrate, and Tf > 10% for large area modules on a glass substrate that exhibit <15% degradation over several hundred hours of constant testing (7). 

Fig. 5. A 90° polished cross section of a production white titania enamel, with the microstructure showing the interface between steel and direct-on enamel as observed by reflected light micrography at 3500 x magnification using Nomarski Interface Contrast (oil immersion). A is a steel substrate B, complex interface phases including an iron—nickel alloy C, iron titanate crystals D, glassy matrix E, anatase, Ti02, crystals and F, quart2 particle.

A multilayer-type structure probably due to cords in the molten zone between single arc sprayed (0.25 MPa) Ni droplets and steel substrate were found in AES point depth profiles [2.158]. That particular arc spraying condition turned out to yield the best adhesion. Plasma-sprayed AI2O3 layers separated from pre-oxidized Ni Substrate had a micrometer-thick NiO layer on the substrate-sided face and micrometer-deep oxide interdiffusion [2.159]. In this work also, AES point depth profiling substantiated technological assumptions about adhesion mechanisms. 

The transient signals from and isotopes were used as the indicators of the steel substrate and Ti and were used as the indicators of the... 

Tsai et al. have also used RAIR to investigate reactions occurring between rubber compounds and plasma polymerized acetylene primers deposited onto steel substrates [12J. Because of the complexities involved in using actual rubber formulations, RAIR was used to examine primed steel substrates after reaction with a model rubber compound consisting of squalene (100 parts per hundred or phr), zinc oxide (10 phr), carbon black (10 phr), sulfur (5 phr), stearic acid (2 phr). 

Polished steel substrates primed with plasma polymerized acetylene films were immersed into a stirred mixture of these materials at a temperature of 155 5°C to simulate the curing of rubber against a primed steel substrate. During the reaction, the mixture was continuously purged with nitrogen to reduce oxidation. At appropriate times between 1 and 100 min, substrates were removed from the mixture, rinsed with hexane ultrasonically for 5 min to remove materials that had not reacted, dried, and examined using RAIR. The RAIR spectra obtained after reaction times of 0, 15, 30, and 45 min are shown in Fig. 13. 

When a plasma polymerized acetylene film on a steel substrate was reacted with the squalene-containing model rubber compound at 155°C for 15 min, a new band assigned to zinc stearate appeared near 1539 cm in the RAIR spectra... 

Fig. 13. RAIR spectra of model rubber compound reacted with plasma polymerized acetylene films on steel substrates for (A) 0, (B) 15, (C) 0 and (D) 45 min. Adapted by permission of Gordon and Breach Science Publishers from Ref. [12].

The XPS survey spectrum of a 75 nm thick film of plasma polymerized acetylene that was deposited onto a polished steel substrate is shown in Fig. 18 [22]. This film consisted mostly of carbon and a small amount of oxygen. Thus, the main peaks in the spectrum were attributed to C(ls) electrons near 284.6 eV and 0(ls) electrons near 533.2 eV. Additional weak peaks due to X-ray-induced O(KVV) and C(KLL) Auger electrons were also observed. High-resolution C(ls) and 0(ls) spectra are shown in Fig. 19. The C(ls) peak was highly symmetric. 

Fig. 18. XPS survey spectrum of a plasma-polymerized acetylene film with a thickness of 75 nm that was deposited onto a polished steel substrate. Reproduced by ptermission of John Wiley and Sons from Ref. [22].

Fig.. 24. Schematic drawing of the visual appearance of the failure surfaces of lap joints prepared from hot-dipped galvanized steel substrates. Reproduced by permission of John Wiley and Sons from Ref. [41].

Fig. 39. Auger depth protile obtained from a plasma-polymerized film on a polished steel substrate after the film was reacted with a model rubber compound for 65 min. Reproduced by permission of Gordon and Breach Science Publishers from Ref [45].

Positive SIMS spectra obtained from plasma polymerized acetylene films on polished steel substrates after reaction with the model rubber compound for times between zero and 65 min are shown in Fig. 44. The positive spectrum obtained after zero reaction time was characteristic of an as-deposited film of plasma polymerized acetylene. However, as reaction time increased, new peaks appeared in the positive SIMS spectrum, including m/z = 59, 64, and 182. The peaks at 59 and 64 were attributed to Co+ and Zn, respectively, while the peak at 182 was assigned to NH,J(C6Hn)2, a fragment from the DCBS accelerator. The peak at 59 was much stronger than that at 64 for a reaction time of 15 min. However,... 

Negative SIMS spectra obtained from plasma polymerized acetylene films on polished steel substrates as a function of reaction time with the model rubber compound are shown in Fig. 45. The most important changes observed in the... 

In recent years there has been a renewed appreciation of potential beneficial effects of roughness on a macroscale. For example Morris and Shanahan worked with sintered steel substrates bonded with a polyurethane adhesive [61]. They observed much higher fracture energy for joints with sintered steel compared with those with fully dense steel, and ascribed this to the mechanical interlocking of polymer within the pores. Extra energy was required to extend and break these polymer fibrils. 

Fig. 7. Adhesion (critical energy release rate, Fc) of zinc coatings to steel substrates effect of steel surface roughness (after Ye et al. [68]).

The seemingly simple question of the relation the characteristics of a mechanically prepared metal surface and adhesion to that surface has sporadically occupied attention for many decades without any very general conclusion being reached [69]. In some recent work, Amada et al. [70,71] grit-blasted a steel substrate, varying the angle between the gun and the specimen surface, and measured the adhesion of a plasma-sprayed alumina coating. They examined profiles of the... 

As discussed above, silane primers have been investigated extensively for adhesive bonding of steel substrates and have been shown to be quite effective, but the extent to which these are in current commercial use is not known. 

In other studies [115], the bond strengths of joints made from steel substrates coated with a variety of oils and waxes ( 6 mg/cm ) and Joined with acrylic adhesive were investigated. Lap-shear strengths up to 15 MPa were obtained with room temperature curing. Very little degradation was seen after 1000 h of... 

Fig. 32. Micrographs of microcyslalline zinc phosphate coatings on (top) A514 and (bottom) A606 steel substrates showing the very different morphologies produced by identical processes [54],...

Paints are complex formulations of polymeric binders with additives including anti-corrosion pigments, colors, plasticizers, ultraviolet absorbers, flame-retardant chemicals, etc. Almost all binders are organic materials such as resins based on epoxy, polyurethanes, alkyds, esters, chlorinated rubber and acrylics. The common inorganic binder is the silicate used in inorganic zinc silicate primer for steel. Specific formulations are available for application to aluminum and for galvanized steel substrates. 

BS7079 1989, Preparation of steel substrates before application of paint and related products ... 

Endoh, M., Influence of Surface Roughness of Mild Steel Substrate on Adhesive Strength of Zinc Sprayed Coatings . Proc. 8th Int. Thermal Spray. Conf., American Welding Society, pp. 492-502 (1976)... 

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