logging in or signing up Welding Metallurgy.ppsx takeyoudown Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite 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: 1315 Category: Entertainment License: All Rights Reserved Like it (3) Dislike it (0) Added: October 08, 2009 This Presentation is Public Favorites: 0 Presentation Description Welding Metallurgy.ppsx Comments Posting comment... By: safecode (12 month(s) ago) good ppt, very useful special in the training Saving..... Post Reply Close Saving..... Edit Comment Close By: mitalisujith (16 month(s) ago) Dear Sir, very nice ppt. can you please share it with me, send a soft copy for study purpose. mitali.sujith@tespl.com Thanks & regards Mitali Saving..... Post Reply Close Saving..... Edit Comment Close By: a43ads (18 month(s) ago) Good PPt...Can I HAve it? Thank you very much Saving..... Post Reply Close Saving..... Edit Comment Close By: dkiraly (18 month(s) ago) I would like to upload this presentation as an additional resource for my metallurgy course. Saving..... Post Reply Close Saving..... Edit Comment Close By: hs1231 (23 month(s) ago) thank you very much i want this ppt Saving..... Post Reply Close Saving..... Edit Comment Close loading.... See all Premium member Presentation Transcript Welding Metallurgy : Welding Metallurgy 6.1 Metals 6.1.1 Metals Structure 6.1.2 Metal Identification 6.2.1 Heat 6.2.1 Distortion 6.2.2 Heat Affected Zone 6.2.3 Pre Heating 6.2.4 Post Heating METALS : METALS Back Most metals are hard, shiny, they feel heavy (dense) and they melt only when they are very hot . Metals are very useful to people. They are used to make tools because they can be strong and easy to shape. Iron and steel have been used to make bridges, buildings, or ships. Some metals are used to make items like coins because they are hard and will not wear away quickly. For example copper (which is shiny and red in color), aluminum (which is shiny and white), gold (which is yellow and shiny) , and silver and nickel (also white and shiny). METAL STRUCTURE : METAL STRUCTURE Back Metals are giant structures of atoms held together by metallic bonds. "Giant" implies that large but variable numbers of atoms are involved - depending on the size of the bit of metal. The structures of pure metals are easy to describe because the atoms can be thought of as identical perfect spheres. These substances all crystallize in one of four basic structures known as simple cubic (SC), body-centered cubic (BCC), hexagonal closest packed (HCP), and cubic closest packed (CCP). METAL IDENTIFICATION : METAL IDENTIFICATION Back Many methods are used to identify a piece of metal. Identification is necessary when selecting a metal for use in fabrication or in determining its weldability. Some common methods used for field identification are surface appearance, spark test, chip test, and the use of a magnet HEAT : HEAT Back In physics and thermodynamics, heat is the process of energy transfer from one body or system due to thermal contact, which in turn is defined as an energy transfer to a body in any other way than due to work performed on the body. When an infinitesimal amount of heat δQ is transferred to a body in thermal equilibrium at absolute temperature T in a reversible way, then it is given by the quantity TdS, where S is the entropy of the body. A related term is thermal energy, loosely defined as the energy of a body that increases with its temperature. Heat is also loosely referred to as thermal energy, although many definitions require this thermal energy to actually be in the process of movement between one body and another to be technically called heat (otherwise, many sources prefer to continue to refer to the static quantity as "thermal energy"). Heat is also known as "Energy". DISTORTION : DISTORTION Back Welding-distortion, deformation, warping, residual welding stresses, fixturing, welding distortion causes, welding localized heat input, reduced yield strength at high temperature, straightening, compensating distortion, stress relieving, welding links, welding tips, improving deformation outcome HEAT AFFECTED ZONE : HEAT AFFECTED ZONE Back Heat affected zone is measured regarding the microstructure changes in the weld. For example in steels this is the area around the weld zone which has undergone a transformation. In other words this is the area which had been austenitized. For calculating the HAZ after welding, for steels it is better to macro etch the section of the weld; HAZ can be easily recognized by the contrast it makes with the base metal and the weld metal. PRE HEATING : PRE HEATING Back The casting must be preheated to at least 900ºF before you begin increasing the temperature in the area you want to braze. The bronze rod will melt at around 1725ºF. A good bonding temperature is 1800ºF. The casting should be positioned so that you are brazing on an incline of at least 30 degrees. Avoid "in position" or flat brazing as this causes pin holes, cold laps, and burnt edges. Brazing uphill allows you to fill the vee from bottom to top in one pass. Small, thin steps allow you to move quickly and keep the area ahead of the puddle tinned. Be sure to post heat to normalize the casting at 900ºF. POST HEATING : POST HEATING Back Post heating is a method to either reduce stresses, anneal or harden. Post-heating are recommended and sometimes necessary to help eliminate common problems that arise including: hydrogen cracking, excessive hardening in the weld zone (high carbon steel alloys), and shrinkage stresses during cooling. You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Welding Metallurgy.ppsx takeyoudown Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite 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: 1315 Category: Entertainment License: All Rights Reserved Like it (3) Dislike it (0) Added: October 08, 2009 This Presentation is Public Favorites: 0 Presentation Description Welding Metallurgy.ppsx Comments Posting comment... By: safecode (12 month(s) ago) good ppt, very useful special in the training Saving..... Post Reply Close Saving..... Edit Comment Close By: mitalisujith (16 month(s) ago) Dear Sir, very nice ppt. can you please share it with me, send a soft copy for study purpose. mitali.sujith@tespl.com Thanks & regards Mitali Saving..... Post Reply Close Saving..... Edit Comment Close By: a43ads (18 month(s) ago) Good PPt...Can I HAve it? Thank you very much Saving..... Post Reply Close Saving..... Edit Comment Close By: dkiraly (18 month(s) ago) I would like to upload this presentation as an additional resource for my metallurgy course. Saving..... Post Reply Close Saving..... Edit Comment Close By: hs1231 (23 month(s) ago) thank you very much i want this ppt Saving..... Post Reply Close Saving..... Edit Comment Close loading.... See all Premium member Presentation Transcript Welding Metallurgy : Welding Metallurgy 6.1 Metals 6.1.1 Metals Structure 6.1.2 Metal Identification 6.2.1 Heat 6.2.1 Distortion 6.2.2 Heat Affected Zone 6.2.3 Pre Heating 6.2.4 Post Heating METALS : METALS Back Most metals are hard, shiny, they feel heavy (dense) and they melt only when they are very hot . Metals are very useful to people. They are used to make tools because they can be strong and easy to shape. Iron and steel have been used to make bridges, buildings, or ships. Some metals are used to make items like coins because they are hard and will not wear away quickly. For example copper (which is shiny and red in color), aluminum (which is shiny and white), gold (which is yellow and shiny) , and silver and nickel (also white and shiny). METAL STRUCTURE : METAL STRUCTURE Back Metals are giant structures of atoms held together by metallic bonds. "Giant" implies that large but variable numbers of atoms are involved - depending on the size of the bit of metal. The structures of pure metals are easy to describe because the atoms can be thought of as identical perfect spheres. These substances all crystallize in one of four basic structures known as simple cubic (SC), body-centered cubic (BCC), hexagonal closest packed (HCP), and cubic closest packed (CCP). METAL IDENTIFICATION : METAL IDENTIFICATION Back Many methods are used to identify a piece of metal. Identification is necessary when selecting a metal for use in fabrication or in determining its weldability. Some common methods used for field identification are surface appearance, spark test, chip test, and the use of a magnet HEAT : HEAT Back In physics and thermodynamics, heat is the process of energy transfer from one body or system due to thermal contact, which in turn is defined as an energy transfer to a body in any other way than due to work performed on the body. When an infinitesimal amount of heat δQ is transferred to a body in thermal equilibrium at absolute temperature T in a reversible way, then it is given by the quantity TdS, where S is the entropy of the body. A related term is thermal energy, loosely defined as the energy of a body that increases with its temperature. Heat is also loosely referred to as thermal energy, although many definitions require this thermal energy to actually be in the process of movement between one body and another to be technically called heat (otherwise, many sources prefer to continue to refer to the static quantity as "thermal energy"). Heat is also known as "Energy". DISTORTION : DISTORTION Back Welding-distortion, deformation, warping, residual welding stresses, fixturing, welding distortion causes, welding localized heat input, reduced yield strength at high temperature, straightening, compensating distortion, stress relieving, welding links, welding tips, improving deformation outcome HEAT AFFECTED ZONE : HEAT AFFECTED ZONE Back Heat affected zone is measured regarding the microstructure changes in the weld. For example in steels this is the area around the weld zone which has undergone a transformation. In other words this is the area which had been austenitized. For calculating the HAZ after welding, for steels it is better to macro etch the section of the weld; HAZ can be easily recognized by the contrast it makes with the base metal and the weld metal. PRE HEATING : PRE HEATING Back The casting must be preheated to at least 900ºF before you begin increasing the temperature in the area you want to braze. The bronze rod will melt at around 1725ºF. A good bonding temperature is 1800ºF. The casting should be positioned so that you are brazing on an incline of at least 30 degrees. Avoid "in position" or flat brazing as this causes pin holes, cold laps, and burnt edges. Brazing uphill allows you to fill the vee from bottom to top in one pass. Small, thin steps allow you to move quickly and keep the area ahead of the puddle tinned. Be sure to post heat to normalize the casting at 900ºF. POST HEATING : POST HEATING Back Post heating is a method to either reduce stresses, anneal or harden. Post-heating are recommended and sometimes necessary to help eliminate common problems that arise including: hydrogen cracking, excessive hardening in the weld zone (high carbon steel alloys), and shrinkage stresses during cooling.