In an effort to seek poly(vinyl formal) (PVFM) foams based wound dressing pad material, a series of foamed PVFM materials have been synthesized under varied conditions. The influence of conditions on the properties of PVFM foam, such as mechanical properties, water absorption, pore structure and bulk density, is well discussed individually. It has been shown that both the reactant and acid catalyst affect the degree and speed of acetalization, therefore the mechanical properties, pores continuity and water absorption of the resultant sample. The addition of Na2CO3, surfactant and CMCNa are mainly influencing the porous structure as well as the mechanical properties and water absorption. One best sample with balanced properties is obtained. It possesses higher mechanical strength and water absorption while the other properties are similar, comparing with a commercial surgical PVFM sponge (YJ-1) currently used.
Surface defects caused by damage or corrosion are major factor in petrochemical pressure vessels and line pipes failure. The characteristic size of typical surface defect is from micron to submillimeter which belongs to mesoscopic scale, leading to difficulties for inspection and evaluation. The instrumented indentation method has widely used in the characterization of micro-zone mechanical behavior which could be effective in surface defects analysis. This paper aims at investigating the correspondence between indentation experimental results and distribution characteristics of surface defects. Mechanical properties of pressure vessel steel with surface defects are measured by indentation, and corresponding finite element models are established. Finite element simulation results of equivalent mechanical properties under indentation and three dimensional deformations are compared, and the applicability of finite element models for indentation test of steel with surface defects is analyzed. The effect of randomized surface defects on measuring result is studied subsequently using stochastic finite element models. The relation of equivalent mechanical properties and description of surface defects is proposed. The achievement could used to estimate the degree of damage or corrosion by miniature indentation testing techniques for safety assessment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.