Melting With Induction Heating

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Overview
Using Induction
Setup
Melting Points
At Work

Melting metals with solid state RF induction heating is usually accomplished by heating the metal in a crucible made from a non-conductive refractory material. The charge of metal within the crucible is melted down to liquid form.

This process is commonly used to produce high quality steels and nonferrous alloys for casting operations. The liquified metal is poured into a cavity having the desired shape. The metal solidifies with a minimum of shrinkage, after which the mold is removed to reveal a finished, machinable product

Modern induction heating provides reliable, repeatable, non-contact and energy-efficient heat in a minimal amount of time. Induction produces circular eddy currents within the molten mass, creating a stirring action which results in a very uniform product. Induction heating provides fast, controllable temperature ramp, allowing for consistent quality results. Both ferrous and non-ferrous alloys can be melted in induction furnaces. The flexibility and cleanliness of induction melting cannot be duplicated by conventional steel mill and foundry methods.

Typical induction furnaces for melting range from 1 to 20kW, depending on the metal and application requirements

setup for induction melting

Aluminum	1220°F
Copper	1981°F
Graphite	6740°F
Iron	2797°F
Molybdenum	4730°F
Nickel	2647°F
Platinum	3217°F
Titanium	3035°F

Reports from the field...

"When I originally quoted the package I promised them that with this new equipment they would see a maximum of 15 minute melt rate. During my visit the customer expressed that they we extremely satisfied with the new equipment and so off to the melt shop we went to time the melt rate and see the performance of our equipment. Everyone on the team was thrilled to see that they were getting a 7 minute melt rate with 12 to 15 pounds of material. Up until now they have been using (a competitor's) 50kW, 3000 Hz power supply with a 30lb furnace and achieving only a 35 minute melt rate."

utm_medium	material	docid	title	blurb	regn_link	pre-reg link	ppc_link	ppc_link_2	post-reg link	onClick download	onClick, View
melting		melting_11	Melting of Ni based alloy samples	Induction heating provides hands-free heating, involves no operator skill required for manufacturing, even distribution of heating and fast, controllable temperature ramp	apps_able.php	melting.php			db_melting.html
melting		melting_10	Heating a crucible for melting plastic	A single-position 6-turn helical coil is used to generate the required heating for application. The crucible is heated in 70 seconds with the 5kW power supply.	apps_able.php	melting.php			db_melting.html
melting		melting_9	Melting silicon in graphite crucible for material testing	The customer is developing a university lab experiment to melt silicon and is still developing the process.	apps_able.php	melting.php			db_melting.html
melting		melting_8	Melting lead ingots to form battery posts and connectors	Melting 30 lb(13.6 kg) & 60 lb(27.2 kg) lead ingots to form battery posts & connectors	apps_able.php	melting.php			db_melting.html
melting		melting_07	Melting the end of a plastic tube to create a seal	A single turn coil encapsulated in custom blocks is used for sealing the tube. Two tubes are placed between the coil blocks and a 7lb (3.2kg) load is applied to the top of the coil.	apps_able.php	melting.php			db_melting.html
melting		melting_6	Crucible melting a variety of materials in a nitrogen atmosphere	The crucible is heated using a coil with a four turn pancake at the base that extends upward into a three turn helical coil.	apps_able.php	melting.php			db_melting.html
melting		melting_05	Melting aluminum in a graphite crucible for casting	Induction heating provides hands-free heating that involves no operator skill for manufacturing, repeatable, dependable results, more efficient and cost effective then gas furnace, does not heat up the manufacturing area and increases production.	apps_able.php	melting.php			db_melting.html
melting		melting_04	Hermetic sealing of stainless steel rods with glass preforms	Induction heating provides hands-free heating that involves no operator skill for manufacturing, amounts of glass are precisely controlled by the glass preforms and even flow of glass creates aesthetically pleasing bond.	apps_able.php	melting.php			db_melting.html
melting		melting_03	Remove plastic coating from steel tubes	Induction heating is the only feasible way to remove the plastic coating, leaving it in an unpolluted form for recycling. It is a faster process	apps_able.php	melting.php			db_melting.html
melting		melting_02	Releasing a Lens Grinding Fixture Bond	The bonded assembly is placed (glass up) within a helical coil which circles the bonding slug. Induction heats the material to the melting point in 5-7 seconds.	apps_able.php	melting.php			db_melting.html
melting		melting_01	Melting of Ticonium and Nobilium ingots	Due to the small size of the ingots, RF induction heating was required to efficiently couple to the samples in order to provide the necessary power to initiate melting.	apps_able.php	melting.php			db_melting.html