Effect of Different Parameters on Glass to Metal Joints used in Solar Systems

Abstract

Solar energy is at the forefront of the global transition to renewable power sources, driven by newlinethe pressing need to meet the energy demands of a growing world population. This shift newlinetowards sustainable alternatives is reshaping the global energy landscape, with solar newlinetechnology which plays a key role in addressing climate change along with energy security newlineconcerns. Possibly, this technology is substantial owing to the abundant and direct solar newlineradiation available, as well as the extensive unoccupied areas that can be utilized for solar newlineenergy harvesting. Typically, solar energy is captured using photovoltaic (PV) panels and newlinevarious concentrating receiver designs including parabolic trough receiver tubes (PTRTs). newlineHowever, in concentrating solar receiver tubes (CSRT), the primary issue leading to failure is newlinethe leakage occurring at the glass-to-metal seal. The disparity between the coefficient of newlinethermal expansion (CTE) of glass tube and the bellows of steel are the major cause of this newlineleakage. newlineIn solar receiver tubes, glass-metal seals are the crucial components for maintaining vacuum newlineintegrity, directly affecting the efficiency of solar thermal power plants. This study investigates newlinethe optimization of glass-metal seals for solar receiver tubes in concentrated solar power (CSP) newlineplants, focusing on improving their performance and integrity. This research examines various newlinefactors affecting seal quality, including material selection, surface preparation, pre-oxidation newlineconditions, and incorporation of nanomaterials. newlineAmerican iron and steel institute (AISI) 304 stainless steel (SS) outperformed AISI 202 for newlineglass-metal seals, with optimal pre-oxidation conditions of 700 °C for 30 minutes in a muffle newlinefurnace, resulting in a weight gain of 0.32±0.005 mg/cm² and a shear strength of 26.8 MPa. newlineUsing an induction furnace significantly reduced the processing time, with the pre-oxidation newlineof AISI 304 at 950 °C for 8 seconds and sealing at 950 °C for 180 seconds achieving a newlinecomparable shear strength of 26.4 MPa.