Surface modification hardening

Surface modification includes change in surface attributes, such as application of (metal) layer(s) and/or hardening. 

Fused-salt electroplating, which is commonly referred to as metal-liding, is a process for surface modification and surface hardening by electrodeposition fiom fused-salt electrolytes. Two unique aspects of this electrodeposition process are (1) elements that cannot be plated by conventional processes may plate by fused-salt electrodeposition and (2) if the deposition rate is controlled to match the diffusion rate of the... 

Surface modification, which involves some change in surface properties, such as application of a metal layer or hardening... 

LPKF Laser Electronics AG has developed ProtoPaint LDS, a process by which virtually any plastic body can be structured by the method known as LPKF-LDS [85,86,105], A paint system based on polyurethanes with an isocyanate hardener and laser-activated additives is applied for the LDS-compatible surface modification of a plastic body produced by rapid prototyping. Known as ProtoPaint LDS, this... 

Laser Hardening and Modification. Lasers are used to surface harden ductile steels and improve the toughness to a depth of 0.35 min or more. Lasers can also be used to bond solid or powder coatings to a surface. Typical coalings are nickel or titanium carbide on iron, and nickel, cobalt, manganese, and titanium carbide. TiC. on aluminum. I1 sc of lasers with other specialized coating methods is common. 

The penetration depth of plasma interaction with a polymer has been estimated to vary between 50A and 10 pm (52). The specific depth of interaction (crosslinking, degradation, chemical modification) depends on both the polymer and the plasma conditions (power, pressure, etc.). Therefore, it would be useful to ascertain the depth and mode of plasma interaction during etching since the resist films are typically a micron or less in thickness. If, for example, the degradation effects are confined to the top few hundred Angstroms of a film, a surface hardening treatment may be all that is required to protect the resist. 

Radiation modification of PC and PSF as plastic teeth was successfully attained by specific irradiation techniques, that is, the irradiation at elevated temperature of the Tg in inert gas atmosphere or under vacuum. The hardness and wear resistance of PC and PSF improved with a small dose of 3-5 kGy, whereas the decay of mechanical properties and coloring were scarce. By applying EB irradiation using the EB accelerator, the gradient of hardness can be formed in PC teeth. Namely, the surface area of teeth could be hardened selectively by the lower voltage of the EB accelerator. 

Another prominent example for accidental microstmcture modification is white layers, more or less thick surface layers in hardened materials. They show a clearly increased hardness and a resistance against etching, so that they appear white in metallographic polished sections. The phenomenon appears in certain machining processes like grinding or hard machining, but also on railroad tracks, as a result of mechanic and thermal influences. Below the white layer, there is also more or less thick, tempered zone with reduced hardness. Microstmctural analyses of white layers lead to different results (Guo and Sahni 2004). 

The application of extrusion and injection molding to the forming of ceramic powders has benefited considerably from the principles and technology developed in the plastics industry. Extruders and molding machines used in the plastics industry are employed but some modification of the machines is required for ceramic systems (e.g., hardening of the contact surfaces). 

An evolution of /r versus slip is also found. A large amount of slip is accompanied by an increase in the COF and the opposite slip is always facilitated compared to the current slip. It is about the kinematic component of the evolution of the COF. This evolution is similar to kinematic hardening for plastic behavior. The kinematic evolution is the result of the degradation of the contact by abrasive weturs, by the modification of the form of the contact surface, by the behavior of the third body, etc. 

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