logging in or signing up windows and glass Susett Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 373 Category: Education License: All Rights Reserved Like it (0) Dislike it (0) Added: January 09, 2008 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Windows and Glass: Windows and Glass Question:: Question: Which window of a car can tolerate the larger stress before breaking? The front windshield The side window They’re equally strongObservations About Windows: Observations About Windows Windows are clear, but window glass looks greenish Window glass breaks if you heat it too rapidly Some older windows aren’t very smooth Some car windows break into tiny pieces Window glass can be bent if you heat it carefullyGlasses: Glasses Amorphous solids No crystal structure No long-range order Resemble “frozen liquids”Forming a Glass: Forming a Glass Requirements Material must have high viscosity at melting point Material must have difficulty nucleating crystal Procedure Melt material to eliminate crystal structure Cool material quickly through melting temperature Form supercooled liquid Cool until solidQuartz: Quartz Quartz is silicon dioxide (silica) Is an excellent network former Slow cooling forms regular network Fast cooling forms irregular network High viscosity at melting point However, nucleates crystals easily Melting point of Quartz is very highSoda-Lime-Silica Glass: Soda-Lime-Silica Glass Adding sodium oxide (soda) lowers melting point Adding calcium oxide (lime) makes it insoluble Sodium and calcium ions terminate the network and soften the glass Soda-lime-silica glass is common glassBorosilicate Glass: Borosilicate Glass Soda-lime-silica glass expands much when heated Breaks easily during heating or cooling Boron-oxide-silica glass expands less Tolerates heating or cooling reasonably well Pyrex and Kimax are borosilicate glassesTempered Glass: Tempered Glass Tempering glass Heat glass to softening point Cool outside of glass quickly Outside stiffens while inside is still hot Shrinking inside compresses outside Compressed outside stretches inside Resists fractures because surface is compressed Crumbles when cracked because inside is tenseQuestion:: Question: Which window of a car can tolerate the larger stress before breaking? The front windshield The side window They’re equally strong You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
windows and glass Susett Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 373 Category: Education License: All Rights Reserved Like it (0) Dislike it (0) Added: January 09, 2008 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Windows and Glass: Windows and Glass Question:: Question: Which window of a car can tolerate the larger stress before breaking? The front windshield The side window They’re equally strongObservations About Windows: Observations About Windows Windows are clear, but window glass looks greenish Window glass breaks if you heat it too rapidly Some older windows aren’t very smooth Some car windows break into tiny pieces Window glass can be bent if you heat it carefullyGlasses: Glasses Amorphous solids No crystal structure No long-range order Resemble “frozen liquids”Forming a Glass: Forming a Glass Requirements Material must have high viscosity at melting point Material must have difficulty nucleating crystal Procedure Melt material to eliminate crystal structure Cool material quickly through melting temperature Form supercooled liquid Cool until solidQuartz: Quartz Quartz is silicon dioxide (silica) Is an excellent network former Slow cooling forms regular network Fast cooling forms irregular network High viscosity at melting point However, nucleates crystals easily Melting point of Quartz is very highSoda-Lime-Silica Glass: Soda-Lime-Silica Glass Adding sodium oxide (soda) lowers melting point Adding calcium oxide (lime) makes it insoluble Sodium and calcium ions terminate the network and soften the glass Soda-lime-silica glass is common glassBorosilicate Glass: Borosilicate Glass Soda-lime-silica glass expands much when heated Breaks easily during heating or cooling Boron-oxide-silica glass expands less Tolerates heating or cooling reasonably well Pyrex and Kimax are borosilicate glassesTempered Glass: Tempered Glass Tempering glass Heat glass to softening point Cool outside of glass quickly Outside stiffens while inside is still hot Shrinking inside compresses outside Compressed outside stretches inside Resists fractures because surface is compressed Crumbles when cracked because inside is tenseQuestion:: Question: Which window of a car can tolerate the larger stress before breaking? The front windshield The side window They’re equally strong