SHS 9290 represents a technical leap in the development of advanced PTAW hardfacing powders since it contains no added tungsten carbide, no nickel and no separate matrix. SHS 9290 is designed to replace and be superior to existing PTAW powders, including industry standard nickel/chromium/boron/silicon types laden with up to 65% tungsten carbide, traditionally used for extreme abrasion resistance. When applied as a PTAW weld overlay, homogenous deposits are produced with extreme resistance to abrasion while maintaining significant toughness. The as-welded deposits contain a high proportion of submicron and near-nano borocarbide phases formed during solidification providing exceptional uniformity of hardness and wear performance across a range of wear environments.

Microstructural Refinement
SHS 9290 allows high undercooling to be achieved prior to nucleation and growth. This results in significant refinement of the microstructure over conventional alloys solidifying via conventional liquid solidification growth modes. In the following photos, SEM backscattered electron micrographs at two magnifications illustrate the differences in the microstructural scale of PTAW hardfacing deposits. SHS 9290 exhibits complex borocarbide phase scales which are much finer than 65% angular tungsten carbide or 60% spherical tungsten carbide deposits. This reduced microstructural scale promotes a highly uniform wear rate throughout the volume of the SHS 9290 deposit. The highly refined (sub micron) structure of SHS 9290 makes the weld overlay deposit much more resistant to fine particle abrasion and erosion since the scale of the microstructure is finer than typical wear erodents (i.e., debris and particles). In contrast, the large scale of angular or spherical tungsten carbide particles in competing materials can lead to preferential wear of the matrix and cracking/pull-out of the hard tungsten carbide particulates.