Uniformity of coatings

Therefore, due to considerations of uniformity of coating, in further tests it was decided to focus on the spheroidal metal-graphite composites. 

Uniformity of coating (tolerance, %) very good good good... 

Very important factors in LCVD are (1) the location of the critically important layer, i.e., the dissociation glow, in a glow discharge, and (2) the location of the substrate with respect to the onion layer structure, i.e., in which layer of an onion structure the substrate is placed. The location of the critical layer depends on what kind of discharge system is employed to create a luminous gas phase. In a strict sense, it is impossible to uniformly coat a substrate placed in a fixed position in a reactor, and the relative motion of a substrate to the onion layer structure of luminous gas phase is a mandatory requirement if high uniformity of coating is required. 

Set. The general flow behaviour of vitreous enamel slip determining the rate of draining, residual thickness, and uniformity of coating. 

The water absorption decreased as the density and uniformity of coating improved, and the water absorption of coating sintered at 1400X3 is as low as 2.6%. 

The appearance of the post-braze surfaces predominantly depends on initial flux loading and uniformity of coating. Once the flux melts, it is completely liquid. In its molten state, the flux has no particles. Once the flux is liquid, it immediately spreads out and wets the surfaces. Upon cooling and solidification, the amount of flux residue and its distribution on the surface of the work-piece is related entirely to the initial flux loading, and not particle size. 

This leads us to discussion of the methods by which the throwing power can be increased. The most common method is to use suitable additives, as discussed in Section 19.3.3. Indeed almost all industrial plating baths contain additives of one kind or another, used to improve the uniformity of coating, as leveling and brightening agents and to relieve internal stress in the deposit. 

---