Secure release plug with fuselable metal and related device and method

Abstract

Pressure relief devices and associated apparatuses, such as vessels, are described that are adapted to provide a pressure relief to a pressurized fluid within a vessel when a fusible metal component of the relief device reaches a melting temperature.

Description

Technical Field

[0001] The following description relates to the field of devices referred to as "plugs" comprising a fusible metal and adapted to provide pressure relief of storage containers at high temperatures. Background Art

[0002] Containers used to store or transport gaseous or liquid materials, sometimes under elevated pressure (greater than atmospheric pressure), may be equipped with a device that allows the interior of the container to pass through to the outside of the container when the container is exposed to dangerously high temperatures, i.e., a "pressure relief device". When the container is exposed to dangerously high temperatures, the pressure relief device creates a through flow path between the interior of the container and the exterior of the container that allows the contents at the interior of the container to be released to prevent the interior from reaching an internal pressure that would cause the container to rupture (i.e., explode). Dangerously high internal pressures within a container may be caused by the container being positioned in a high temperature environment (e.g., due to a fire). If the container is subject to a fire, the temperature of the container and the pressure relief device will increase, and when the device reaches a certain temperature, the device creates an opening from the inside to the outside that allows the pressure at the interior of the container to be safely reduced to prevent an explosion. Several types of pressure relief devices have been used to prevent overpressure from accumulating within a container, however, it is necessary to avoid contamination of the contents of the container due to leaching of the material of the relief device. Summary of the invention

[0003] Raw material gases and liquids provided to industry include products contained, stored, and transported in metal tanks that are constructed to contain raw material liquids or gases, optionally under pressure. Many types of raw materials stored in these metal tanks are used in processes that require the raw materials to be in high purity form. When raw materials are contained, stored, or transported in metal tanks, the tanks should not introduce any new contaminants to the raw materials.

[0004] Many metal cans contain a pressure relief device in the form of a plug containing a fusible metal such as tin, bismuth, lead or cadmium. The fusible metal of the plug contacts the raw material contained in the can and becomes a potential source of contamination by leaching into the liquid or gaseous raw material contained in the can.

[0005] The amount of fusible metal that can be added to the raw materials by leaching can be very small, for example, at the part per million level or lower. But even this very low level of metal contaminants added to the raw materials from metal storage tanks during storage or transportation can cause deleterious effects in the specific process in which the raw materials are used. For example, various types of raw materials used in microelectronics and semiconductor manufacturing processes are used in very high purity. Some of these gaseous and liquid raw materials are stored and transported in metal tanks that contain pressure release devices (which contain fusible metals). Examples of these types of raw materials are organometallic compounds, such as metal amides, metal alkyls (e.g., n-butyl lithium), and aryl metals. Other examples are silanes, such as halosilanes, such as chlorosilanes.

[0006] Metallic (e.g., heavy metal) contaminants such as tin, bismuth, cadmium, lead, etc., when present in these types of raw material fluids, can have measurable deleterious effects on the processes that use these materials to manufacture semiconductor products, microelectronic devices, and the like. The presence of heavy metal contaminants such as bismuth or tin can affect the yield of the process, the performance properties of devices made using the process, or both.

[0007] The present disclosure relates to a thin coating of an inert barrier material at the surface of a fusible metal plug for isolating the metal material (e.g., heavy metal) of the fusible metal plug from the raw material contained in a container. The coating should be thin enough not to prevent the fusible metal material from properly acting as a pressure relief device by melting and flowing at high temperatures to release the pressure within the container. Example coatings may be of a chemically inert material such as a metal (e.g., nickel), a metal oxide (Al or Y based), or a perfluorocarbon (e.g., polytetrafluoroethylene) and may be applied to the plug by a deposition technique such as chemical vapor deposition, physical deposition, atomic layer deposition for metal oxides; electrodeposition for metals; or a coating technique such as dip coating, brush coating, spray coating, or the like for fluorocarbon coatings.

[0008] In one aspect, the present disclosure is directed to a pressure relief device in the form of a plug. The plug includes: a plug body; a flow path extending through the plug body between a first flow path end and a second flow path end; a fusible metal body received in the flow path, the metal body including a first metal body end and a second metal body end; and a coating at a surface of the metal body at the first metal body end.

[0009] In another aspect, the present disclosure relates to a container. The container includes a container wall, an enclosed container interior, and a plug. The plug includes: a plug body; a flow path extending through the plug body between a first flow path end and a second flow path end; a fusible metal body contained in the flow path, the metal body including a first metal body end and a second metal body end; and a coating at a surface of the metal body at the first metal body end.

[0010] In yet another aspect, the present disclosure relates to a method of making a plug. The plug includes: a plug body; a flow path extending through the plug body between a first flow path end and a second flow path end; a fusible metal body contained in the flow path, the metal body including a first metal body end and a second metal body end; and a coating at a surface of the metal body at the first metal body end. The method includes applying the coating to the surface at the first metal body end. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1A and 1B Display the described example pressure relief device.

[0012] Figure 2A and 2B The described example pressure relief device is shown as part of a fluid delivery valve.

[0013] Figure not to scale. DETAILED DESCRIPTION

[0014] The following description relates to a pressure relief device called a "plug", which includes a plug body, a flow path within the plug body, and a fusible metal body that blocks the flow path. The fusible plug melts at high temperature and the flow path is broken through to allow fluid to flow through the flow path.

[0015] When the plug is installed as part of the container, the flow path extends between the interior of the container and the exterior of the container. In a state of normal use, the container, the plug and the fusible metal body are at about ambient temperature, which is below the melting temperature of the fusible metal, thus keeping the fusible metal in a solid form. The fusible metal body is positioned in the flow path, thereby blocking the flow path and preventing fluid from flowing through the flow path of the plug.

[0016] At high temperatures, such as those that may occur during a fire, a fusible metal body that would normally (at ambient temperature) block the flow path will melt and flow out of the flow path to cause the flow path to become open between the ends of the flow path. At high temperatures, liquid fluids in a container become gaseous, and gaseous fluids at high temperatures create high internal pressures in the container. At high temperatures, the opening of the flow path through the molten plug of the fusible metal body allows fluid (e.g., gas) to escape from the interior and prevents the interior from becoming pressurized to dangerous levels that would otherwise cause the container to explode.

[0017] The fusible metal body is made of a metal alloy that is "fusible," meaning that the metal alloy "melts" or melts at a relatively low temperature than many other metals and metal alloys. Examples of fusible metal bodies may be made of a metal or metal alloy that includes bismuth, tin, lead, cadmium, or a combination of these. As used herein, an example fusible metal body may have a melting point below about 400 degrees Fahrenheit, for example, a melting point in the range of from 150 degrees Fahrenheit to 400 degrees Fahrenheit. The main constituents of a particular known fusible metal alloy are bismuth, tin, lead, and optionally cadmium in various combinations and relative amounts, and the particular known fusible metal alloy has a melting point of 165 degrees Fahrenheit, 212 degrees Fahrenheit, 283 degrees Fahrenheit, and 300 degrees Fahrenheit.

[0018] In these types of pressure relief devices, the fusible metal body of the plug is typically directly exposed to the gaseous or liquid contents at the interior of the container and directly contacts the gaseous or liquid contents of the container. Some of the materials stored in these types of containers include materials used in processes that require very high purity for the process and raw materials used in the process. Containers used to store and transport raw materials that must be used in high purity should not introduce any contaminants to the raw materials.

[0019] As identified herein, metallic material of a fusible metal used as part of a pressure relief device may leach into a gas or liquid material stored or transported in a container that holds the pressure relief device. The fusible metal may include tin, bismuth, lead, or other metallic or heavy metal components. The fusible metal contacts the raw materials at the interior of the container and constitutes a potential source of contamination through any of the metallic species that may leach into the liquid or gas material during contact.

[0020] The amount of fusible metal that can be leached into the raw materials as an added contaminant can be very small, for example, at the part per million level or lower. But even this very low level of metal contaminant added to a particular type of raw material can have a deleterious effect in the particular process in which the raw material is used. For example, various types of raw materials used in microelectronics and semiconductor manufacturing processes are used in very high purity. Some of these gaseous and liquid raw materials are stored and transported in metal containers (sometimes called "tanks" or "pressure tanks") that contain pressure release devices, which contain fusible metals that allow the contents of the tank to escape when the tank is exposed to dangerously high temperatures to prevent pressure buildup. Examples include organometallic compounds such as metal amides, alkyl metals (e.g., alkyl lithium compounds, such as n-butyl lithium) and aryl metals (e.g., aryl lithium compounds) and silanes (e.g., halosilanes, such as chlorosilanes).

[0021] If these types of raw materials contain heavy metal contaminants such as tin or bismuth, then when used in semiconductor or microelectronic device processing, the contaminants can have a measurable detrimental effect on the process. The presence of heavy metal contaminants such as bismuth or tin can affect the yield of the process or the performance of the device made using the process.

[0022] As described herein, a pressure relief device (e.g., a "plug") comprising a fusible metal body positioned within a flow path of the device further comprises a coating on a surface of the fusible metal body. The coating is placed on the surface of the fusible metal body and when the pressure relief device is mounted on a container filled with a gas or liquid material, the fusible metal body will be exposed to the interior of the container and will contact the gas or liquid material contained at the interior. The coating is adapted to prevent the metal material of the fusible metal body from being directly exposed to the interior of the container in which the plug is mounted and to prevent contact between the fusible metal body and the contents of the container interior. The coating acts as a physical barrier between the fusible metal body and the contents of the container to prevent a certain amount of fusible metal from potentially leaching into the gaseous or liquid contents of the container, where any such metal material would be considered a contaminant.

[0023] The coating is a thin chemically inert barrier layer placed on the surface of the fusible metal body of the plug to isolate the material of the fusible metal body (which may be a heavy metal such as tin, bismuth, or other metal or heavy metal species) from the gaseous or liquid material held inside the container.

[0024] While the coating is effective as a barrier layer between the fusible metal body and the contents of the container, the coating is also designed to allow the fusible metal body to act as part of a pressure relief device. The fusible metal body having the coating at the surface should remain capable of melting and flowing out of the flow path of the plug when exposed to a sufficiently high temperature to clear the flow path and allow gas or liquid at the interior of the container to escape from the container through the through flow path, thereby avoiding dangerous pressure buildup within the container.

[0025] The coating may be made of any material and may be applied by any method that allows the material of the coating to form a barrier layer at the surface of the fusible metal body in a form that does not excessively affect the function of the fusible metal body (for example, when the fusible metal body melts at a high temperature, it does not prevent the fusible metal body from effectively flowing from the flow path to clear the flow path).

[0026] Example materials for the coating include chemically inert materials such as metal oxides (e.g., based on aluminum or yttrium), metals (e.g., nickel) or metal alloys, fluorides such as fluoropolymers or perfluoropolymers (e.g., ).

[0027] Example coatings can be applied to the surface of the fusible body by any technique that can be used to form the described effective coatings. Useful techniques include deposition techniques such as chemical vapor deposition (and its variants, such as plasma-assisted chemical vapor deposition), atomic layer deposition, sputtering, and electrodeposition. Other useful techniques include coating techniques such as brushing, spraying, and dipping. Useful techniques can be selected based on factors such as the desired thickness of the coating and the desired material of the coating. To deposit a pure metal such as nickel as a coating, the selected technique can be electrodeposition. To deposit an oxide such as aluminum oxide or yttrium oxide, the selected technique can be atomic layer deposition or chemical vapor deposition. To deposit a fluoropolymer, the fluoropolymer can be formed into a liquid by dissolving the fluoropolymer in a solvent or by heating the fluoropolymer to above the melting temperature, and the liquid can be applied to the surface by brushing, dipping, spraying, or another useful coating technique.

[0028] The coating may have a thickness that enables the coating to be used as a barrier layer that inhibits or prevents a certain amount of metal of the fusible metal body from transferring from the fusible metal body to the gaseous or liquid material of the coating contacting the surface of the fusible metal body when placed on the surface of the fusible metal body. The coating is also sufficiently thin and has mechanical properties that do not unduly adversely affect the function of the pressure relief device to allow pressure to be released from the container at high temperatures.

[0029] Example thicknesses of coatings may also depend on the type of coating and the process used to apply the coating. As a general range, useful coatings may have a thickness in the range of from 100 angstroms to 2 microns, such as from 500 angstroms to 1 micron.

[0030] The pressure relief device may be in the form of a plug including a plug body, which may be installed as part of a fluid dispensing valve, for example, when the plug is used to close and seal an opening in a sidewall structure of a container; or as part of any other fluid control or fluid handling device or apparatus. The plug may include a plug body, a flow path extending through the plug body, a fusible metal body within the flow path, and a coating on a surface of the fusible metal body.

[0031] The plug body may include a mechanical engagement that allows the plug body to be securely connected to a component of a container, a flow control valve, a conduit, etc. Useful mechanical engagements may be, for example, a threaded engagement between the container and the plug body, a flange, a press fit, a variable press fit, or a comparable mechanical structure that allows secure engagement of the plug body with a container, a valve, a conduit (e.g., a pipe), or another component of a container or flow control structure.

[0032] An example pressure relief device in the form of a plug includes: a cylindrical plug body including a mechanical joint at an outer surface of the plug body; and a flow path extending through the plug body along the length of the cylindrical plug body from a first flow path end at one end of the cylindrical plug body to a second flow path end at a second end of the cylindrical plug body. In a normal "plug" use state of the pressure relief device, a solid (at room temperature) fusible metal body positioned within the flow path blocks the space of the flow path between the ends of the flow path and prevents any fluid from flowing through the flow path. The fusible metal body includes two ends, one of which is disposed toward the first end of the flow path and the second fusible metal body end is disposed toward the second end of the flow path. A coating is positioned on a surface of the fusible metal body at one of the two ends of the fusible metal body (specifically, at the end that will be exposed to the interior of a container or flow control device).

[0033] Figure 1A An example of the described pressure relief device (i.e., "plug") is shown as part of a container containing liquid or gaseous raw materials in highly purified form. The plug 100 includes a cylindrical plug body 110, which includes a flow path 112 having a first flow path end 114 and a second flow path end 116. A fusible metal body 120 is contained within the flow path 112, and when the plug 100 is in ambient temperature conditions, the fusible metal body 120 is in a solid form to prevent any fluid 130 contained in a container 132 from flowing through the flow path 112. Also as illustrated, the fusible metal body 120 includes a first fusible body end 124 oriented toward the first flow path end 114 and a second fusible body end 126 oriented toward the second flow path end 116. The described inert coating 128 is positioned on the surface of the first fusible body end 124. A mechanical engagement 140 at an outer surface of the plug body 110 engages a corresponding mechanical engagement surface of a sidewall of the container 132; as illustrated, the mechanical engagement is an opposite threaded engagement.

[0034] As in Figure 1A As illustrated, the fusible metal body 120 is in a solid (unmelted) condition and fills the flow path 112 to prevent any fluid 130 from flowing through the plug body 110. The coating 128 is a coating described herein that acts as a physical barrier between the surface of the first fusible body end 124 and the gas 130 at the interior of the container 132.

[0035] As in Figure 1BAs shown, the container 132 and the plug 100 are at high temperatures (e.g., temperatures in the atmosphere of a fire), which can cause the liquid contents of the container to vaporize to cause the internal container pressure to increase. The fusible metal body 120 has melted and has flowed out of the flow path 112 to penetrate the flow path 112 to allow the gaseous fluid 130 to escape from the interior of the container 132 through the flow path 112. Allowing the fluid 130 to escape from the interior of the container 132 prevents pressure buildup that would otherwise occur due to the increase in the temperature of the fluid 130 due to the fire and prevents catastrophic pressure failure and explosion of the container 132 due to excessive pressure at the interior.

[0036] As a different example of the described pressure relief device (e.g., a "plug"), the plug may include a plug body, which is part of a larger valve body that includes a fluid dispensing valve that can be used to dispense fluid from a container while also housing the pressure relief device. The fluid dispensing valve can have any design, but can be particularly designed for conveying high purity gaseous fluids from a container to a processing device (e.g., to a deposition device). The deposition device can be a deposition device for performing atomic layer deposition, chemical vapor deposition, sputtering, or the like. The valve can include a valve body connected to the container, a dispensing port that can be connected to a part of the processing device, and a pressure relief device (e.g., a plug) that can have a design that can engage and disengage the valve body.

[0037] Figure 2A An example of the described pressure relief device (i.e., "plug") is shown included in a larger valve device 201 installed at the outlet of a container containing liquid or gas raw materials in highly purified form. The valve device 201 includes a valve body 202, which includes a valve handle 204, a valve stem 206, and a valve actuator 208. The valve handle 204 can be rotated to rotate the stem 206, which responsively causes the valve actuator 208 to move between an open position and a closed (as illustrated) position. In the open position, gas 230 can flow through the valve body 202 and exit the valve body 202 through the dispensing port 222 for dispensing to a processing device (not shown).

[0038] The valve device 201 includes a plug 200, which is an example of a plug of the present description. As shown, the plug 200 includes a cylindrical plug body 210, which includes a flow path 212 having two ends. A fusible metal body 220 is contained within the flow path 212, and when the plug 200 is in an ambient temperature condition, the fusible metal body 220 is in a solid form to prevent any fluid 230 contained in a container 232 from flowing through the flow path 212. The fusible metal body 220 includes a first fusible body end oriented toward the first flow path end and a second fusible body end oriented toward the second flow path end. The inert coating 228 described (not to scale) is positioned on the surface of the first fusible body end. A mechanical engagement 240 at an outer surface of the plug body 210 engages a corresponding mechanical engagement surface of the valve body 202; as illustrated, the mechanical engagement is an opposite threaded engagement.

[0039] As in Figure 2A As illustrated, the fusible metal body 220 is in a solid (unmelted) state and fills the flow path 212 to prevent any fluid 230 from flowing through the plug body 210. The coating 228 is a coating described herein that acts as a physical barrier between the surface of one end of the fusible body 220 and the gas 230 at the interior of the container 232.

[0040] As in Figure 2B As shown, the container 232 and the plug 200 are at high temperatures (e.g., temperatures in the atmosphere of a fire), which can cause the liquid contents of the container to vaporize to cause the internal container pressure to increase. The fusible metal body 220 has melted and has flowed out of the flow path 212 to penetrate the flow path 212 to allow the gaseous fluid 230 to escape from the interior of the container 232 through the flow path 212. Allowing the fluid 230 to escape from the interior of the container 232 prevents pressure buildup that would otherwise occur due to the increase in the temperature of the fluid 230 due to the fire and prevents catastrophic pressure failure and explosion of the container 232 due to excessive pressure at the interior.

[0041] The pressure relief device described may alternatively include a portion of a different type of container, valve, conduit (e.g., pipe), connector, or any other flow control device or structure for storing, containing, or controlling the flow of gaseous or liquid raw materials. Examples include pipe joints, half-pipe joints and other pipes, conduits or connectors, pressure regulators, pressure relief valves, etc.

[0042] A container including a pressure relief device may be any type of container that can be used to store, transport, deliver, or dispose of a liquid or gaseous fluid and that may incorporate a pressure relief device for safety purposes. In general, a container may be any type of enclosed vessel or conduit including an interior for containing or controlling a liquid or gas in a pressurized or non-pressurized condition. Examples include vessels sometimes referred to as cylinders, barrels, cans, and the like.

[0043] The interior of the container at ambient temperature (e.g., at 23° C.) can contain the liquid or gas, or both, that the container is designed to contain at any pressure conditions. The internal pressure of the container can be below atmospheric pressure, above atmospheric pressure (e.g., at pressure conditions up to or exceeding 20 psi, 50 psi, 100 psi, 500 psi, or 1000 psi), or can be approximately equal to atmospheric pressure, for example, in the range of from 0.7 atmospheres (absolute) to 1.3 atmospheres.

[0044] An example container may be of a type that includes a steel (e.g., carbon steel, stainless steel, etc.) sidewall for containing gas under pressure and a valve or outlet to which a dispensing valve may be attached to allow the gaseous contents to be delivered from the container. The container may be of a type that includes welded seams or does not include any seams (i.e., "seamless").

[0045] The container may be of a standard or approved design, for example, of the type used to contain and transport propane for consumer sale. These may be rated for a "working pressure" of 260 psi.

[0046] Example containers may meet specific specifications of the United States Department of Transportation, such as specified as DOT-4BW260 or in Canada as TC-4BWM18.

[0047] Example containers may have any useful internal volume, for example, may have an internal volume from 10 liters to 500 liters, such as from 20 liters or 50 liters up to 200 liters, 300 liters or 400 liters.

[0048] The container can be designed to hold a high purity fluid (liquid or gas) while minimizing the potential introduction of impurities into the fluid. These can be polymers or inert materials (e.g., fluoropolymers, e.g., perfluoropolymers, such as polytetrafluoroethylene (e.g., )) is the lining.

[0049] In a first aspect, a plug is disclosed herein, comprising: a plug body; a flow path extending through the plug body between a first flow path end and a second flow path end; a fusible metal body received in the flow path, the metal body comprising a first metal body end and a second metal body end; and a coating at a surface of the metal body at the first metal body end.

[0050] In a second aspect according to the first aspect, the coating comprises a metal, a metal oxide or a fluoropolymer.

[0051] In a third aspect according to any of the preceding aspects, the fusible metal body has a melting point in the range of from 150 degrees Fahrenheit to 400 degrees Fahrenheit.

[0052] In a fourth aspect according to any of the preceding aspects, at a temperature between 150 degrees Fahrenheit and 400 degrees Fahrenheit, the fusible metal body melts and flows from the flow path in a molten state to penetrate the flow path between the first flow path end and the second flow path end.

[0053] In a fifth aspect according to any of the preceding aspects, the coating allows the meltable metal body to flow from the flow path in a molten liquid path to penetrate the flow path.

[0054] In a sixth aspect according to any of the preceding aspects, the fusible metal body comprises bismuth, tin, lead, cadmium or a combination thereof.

[0055] In a seventh aspect according to any of the preceding aspects, the coating has a thickness in the range from 100 angstroms to 2 microns.

[0056] In an eighth aspect according to any of the preceding aspects, the plug body comprises an outer surface comprising an engagement selected from a threaded engagement, a flange, and a press fit.

[0057] In a ninth aspect, disclosed herein is a pressure relief device comprising a plug according to any of the preceding aspects.

[0058] In a tenth aspect according to the ninth aspect, the pressure relief device is selected from the group consisting of a pressure relief valve, a conduit, a connector, a pressure regulator, a pipe, a conduit, a connector, a pipe joint and a half pipe joint.

[0059] In an eleventh aspect, disclosed herein is a container comprising: a container wall; enclosing the container interior; and a plug according to any one of the first to eighth aspects.

[0060] In a twelfth aspect according to the eleventh aspect, the plug body engages the container at a side wall.

[0061] In a thirteenth aspect according to the eleventh or twelfth aspect, the plug body engages the container at a pressure relief device selected from the group consisting of a pressure relief valve, a conduit, a connector, a pressure regulator, a pipe, a conduit, a connector, a pipe joint and a half pipe joint.

[0062] In a fourteenth aspect according to any one of the eleventh to thirteenth aspects, the coating is exposed inside the container.

[0063] In the fifteenth aspect according to any one of the eleventh to fourteenth aspects, it further includes an organic metal compound or a silane disposed in the interior of the container.

[0064] In the sixteenth aspect according to any one of the eleventh to fifteenth aspects, it further includes a metal amide, a metal alkyl, or a metal aryl disposed in the interior of the container.

[0065] In the seventeenth aspect according to any one of the eleventh to eighteenth aspects, it further includes an organometallic alkyl lithium disposed in the interior of the container.

[0066] In an eighteenth aspect, disclosed herein is a method for preparing a plug, comprising: placing a fusible metal body in a flow path extending through the plug body between a first flow path end and a second flow path end, the metal body comprising a first metal body end and a second metal body end; and coating a surface of the metal body at the first metal body end with a coating.

[0067] In a nineteenth aspect according to the eighteenth aspect, the coating is applied to the surface by a deposition method selected from chemical vapor deposition, atomic layer deposition, physical vapor deposition and electrodeposition.

[0068] In the twentieth aspect according to the eighteenth or nineteenth aspect, the coating is a metal oxide coating applied to the surface by chemical vapor deposition, physical vapor deposition, or atomic layer deposition.

[0069] In a twenty-first aspect according to the eighteenth or nineteenth aspect, the coating is a metal coating applied to the surface by electrodeposition.

[0070] In a twenty-second aspect according to the eighteenth or nineteenth aspect, the coating comprises a fluoropolymer and the coating is applied to the surface by a coating method selected from brush coating, spray coating, and dip coating.

Claims

1. A plug, comprising: a plug body; a flow path extending through the plug body between a first flow path end and a second flow path end; a fusible metal body received in the flow path, the metal body comprising a first metal body end and a second metal body end; and A coating is provided at a surface of the metal body at the first metal body end.

2. The plug of claim 1, wherein the coating comprises a metal, a metal oxide or a fluoropolymer.

3. The plug of claim 1, wherein the fusible metal body has a melting point in the range of from 150 degrees Fahrenheit to 400 degrees Fahrenheit.

4. The plug of claim 1, wherein at a temperature between 150 degrees Fahrenheit and 400 degrees Fahrenheit, the fusible metal body melts and flows from the flow path in a molten state to extend the flow path between the first flow path end and the second flow path end.

5. The plug according to claim 1, wherein the coating allows the fusible metal body to flow from the flow path in a molten liquid path to penetrate the flow path.

6. The plug of claim 1, wherein the fusible metal body comprises bismuth, tin, lead, cadmium, or combinations thereof.

7. The plug of claim 1, wherein the coating has a thickness in a range from 100 angstroms to 2 microns.

8. The plug of claim 1, wherein the plug body includes an outer surface including an engagement selected from a threaded engagement, a flange, and a press fit.

9. A pressure relief device comprising the plug according to claim 1.

10. The pressure relief device of claim 9, wherein the pressure relief device is selected from the group consisting of a pressure relief valve, a conduit, a connector, a pressure regulator, a pipe, a conduit, a connector, a pipe joint, and a half pipe joint.

11. A container comprising: container wall; Enclose the interior of the container; and A plug comprising: a plug body; a flow path extending through the plug body between a first flow path end and a second flow path end; a fusible metal body received in the flow path, the metal body comprising a first metal body end and a second metal body end; and A coating is provided at a surface of the metal body at the first metal body end.

12. The container of claim 11, wherein the plug body engages the container at a side wall.

13. The container of claim 11, wherein the plug body engages the container at a pressure relief device selected from the group consisting of a pressure relief valve, a conduit, a connector, a pressure regulator, a pipe, a conduit, a connector, a pipe joint, and a half-pipe joint.

14. The container of claim 11, wherein the coating is exposed inside the container.

15. The container of claim 11, further comprising an organometallic compound or a silane disposed in an interior of the container.

16. The container of claim 11, further comprising a metal amide, metal alkyl, or metal aryl disposed in an interior of the container.

17. The container of claim 11, further comprising an organometallic alkyl lithium disposed in an interior of the container.

18. A method of preparing a plug, comprising: placing a fusible metal body in a flow path extending through the plug body between the first flow path end and the second flow path end, the metal body including a first metal body end and a second metal body end; and A coating is applied at a surface of the metal body at the first metal body end.

19. The method of claim 18, wherein the coating is applied to the surface by a deposition method selected from the group consisting of chemical vapor deposition, atomic layer deposition, physical vapor deposition, and electrodeposition.

20. The method of claim 18, wherein the coating is a metal oxide coating applied to the surface by chemical vapor deposition, physical vapor deposition, or atomic layer deposition.

21. The method of claim 18, wherein the coating is a metallic coating applied to the surface by electrodeposition.

22. The method of claim 18, wherein the coating comprises a fluoropolymer and the coating is applied to the surface by a coating method selected from the group consisting of brushing, spraying, and dipping.

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