Plastics Today spoke to Patrick Haney, R&D engineer at MTD, about how fluid flow behaves differently in micromolding than it does in conventional injection molding, and how many of the typical flow-management tools used by plastics processors cease to work. Patrick reviews how fluid flow, or rheology, is a critical issue in producing micro parts in their latest article.
“In micro, it is realistic that you reach an ultimate sheer thinning threshold,” Haney said. “After that point, the polymer viscosity stops decreasing with increasing pressure. Once that happens, many tricks and tools of the trade a processor uses to fill thin walls or troubleshoot don’t apply anymore.”
Patrick Haney, R&D Engineer