Dynamic Impact Response of Nanosized Precipitates Bearing Waspaloy

Abstract

Dynamic response of nanosized precipitates bearing (NPB) Waspaloy, a class of superalloy, is crucial to design structural components for critical rotating applications and other severe dynamic impact predisposed applications. The focus of this study is, therefore, to investigate the compressive dynamic behaviour of NPB Waspaloy at a high strain rate under various deformation conditions. The technique of modified split Hopkinson pressure (MSHP) bar was implemented through impact deformation of Waspaloy under wide-ranging deformation temperatures (-180 - 750 oC) and strain rates of (4*103 - 7.5*103 s-1). The outcomes of the experiments divulge how to flow stress relates directly to strain rate and is inversely proportional to deformation temperatures. Work hardening rate affects NPB Waspaloy maximally at the iciest deformation temperature (-180 oC) and the highest strain rate (7.5*103 s-1) considered. Under high straining and high rate of straining deformation conditions, the rate with which work-hardening occurs is destabilized due to the thermal softening effect during deformation. It is established that when strain is constant, the flow stress dependency on the rate of straining depicts linear relation. The thermal softening effect on NPB Waspaloy is concerted at around extreme strain rate (7.5*103 s-1) and iciest deformation temperatures within -180 ~ 25 oC. Mapping of strain, strain rate and deformation temperatures representing input parameters with the resultant flow stress provide an unambiguous analytical view of the effects of dynamic impact deformation. Flow stresses at elevated temperatures are correlated directly with grain growth, mainly influenced by adopted deformation temperatures.

Investigating the high-impact deformation behavior of induced-nano precipitation hardened in718 alloy

“…More importantly, 3D deformation data mapping also stress as strain increases is evident. Moreso, holding deformation temperatures constant enables the investigation into the effect of strain and strain rate on the deformation properties of NPH-718 alloy confirms the fact that flow stress rises with increased cooling during deformation [23]. Obviously, charting NPH-718 alloy deformation behavior at varied deformation conditions implemented in this study yields a more descriptive and enhanced analysis owing to an increased volume of available data.…”

“…Similar trend occurs in the flow stress-strain characteristics of IN 718 as contained in Figure 9(a-d). It is evident that the latter recorded higher temperature rise, ∆T when benchmarked with Waspaloy of [23], almost in all the dynamic impact conditions.…”

“…implemented on stress data of Ti-6Al-2Zr-1Mo-1V alloy with diverse strains, strain rates and temperatures [23]. Moreover, very suitable 3D data mapping has also been implemented on dynamically deformed nickel-based waspaloy to further examine the effect of flow stress, strain, deformation temperature, and strain rate [23].…”