JP3054193B2 - Induction skull spinning of reactive alloys - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for rapid solidification of reactive metals and alloys; more particularly, a molten metal stream through which a rapid moving cooling substrate is deposited. Induction skull melting system with a nozzle to form a rapidly solidified continuous metal filament or ribbon
system).

2. Brief Description of Prior Art Rapid solidification has become an important method for manufacturing vibration materials. The properties of materials produced by rapid solidification are often superior to those of similar materials processed at slower solidification rates. Rapid solidification of the material has improved the physical, mechanical, and corrosion resistance of various alloy systems.

Rapid solidification processes developed to produce practically sufficient quantities of materials fall into two broad categories: atomization and melt spinning. In the atomization process, a stream of molten metal is broken up into fine droplets that cool quickly and solidify as a fine powder suitable for subsequent solidification into a lump article. Melt spinning methods, including cooling block melt spinning and planar flow casting, are directed at a molten alloy stream onto a cooled substrate, which solidifies as a thin foil or ribbon, which Or they can be used in ribbon form or mechanically pulverized into powder for subsequent agglomeration. Common to each rapid solidification category method is the need for a crucible that melts and holds the metal in a molten state, and a flow controller or nozzle that forms and controls the flow of the molten metal.

Rapid solidification attempts initially focused on iron-based, nickel-based, aluminum-based, and magnesium-based alloys. For these alloy systems, a wide variety of refractory materials are used that are non-reactive with the molten metal and are therefore suitable for use as crucibles and nozzles. Subsequently, there was considerable interest in the rapid solidification of reactive alloys, particularly titanium and titanium aluminide. Because these alloys are reactive, conventional melting and casting techniques using refractory crucibles result in unacceptably high levels of contamination due to melting of the crucible.

Various methods have been developed for melting and casting titanium, titanium aluminide and other reactive alloys for conventional ingots. Generally, each of these methods uses a low temperature crucible. The alloy is melted in a crucible made of a material with high thermal conductivity, usually water-cooled copper, so that a solid alloy skull is formed between the molten alloy and the crucible, and the reaction between the alloy and the crucible Block. There are many ways in which the energy needed to melt and hold the alloy in the molten state can be provided, including consumable or non-consumable electrode arc melting, plasma arc melting, or electron beam melting.

The rapid solidification process requires the formation and control of a relatively narrow stream of molten metal, so conventional melting and casting techniques cannot be used for rapid solidification of reactive metals. To address this problem, low-temperature hearth melting has been applied to the rapid solidification of reactive alloys. In the low temperature hearth method, the alloy is melted in a copper hearth with a hole in the bottom. To melt the hearth metal pool, a non-consumable tungsten arc is used. When a sufficiently large metal pool is formed, the skull over the orifice melts and penetrates and the metal forms a metal stream through the orifice. The molten metal flow is controlled by the size of the orifice and the hearth is pressurized against the orifice outlet for additional control. The metal stream is then atomized or directed onto a rapidly moving water-cooled substrate to form a rapidly solidified ribbon. Arc melting with controlled casting from the bottom of the hearth is often employed to produce rapidly solidified powders by atomization and rapidly solidified ribbons by melt spinning. SHWhang, "Rapidly Solidified Ti Alloys with New Additives", Journal of Metals, April 1984, 34-40.
page. Rhowe, Amoto (RGRowe, RAAmoto), "Spinning of Titanium Alloy", Processing of Structure Materials, Ed. Frows and Savige (FHFroes, SJSavage), ASM International, 1987, pp. 253-260.

One of the major limitations of the arc melting spinning or arc melting atomization method is that processing other than small batches of material is difficult. The largest batches of titanium alloys cast to date by these methods are on the order of 1 kg. These methods require the use of an arc to melt through the skull at the bottom of the melt pool, which limits the depth of the pool and is therefore difficult to scale up. Increasing the melting capacity can only be achieved by increasing the hearth diameter, but there is also a limit to the amount of metal that can be melted by a single arc and held in a molten state.

The advantages of melting and casting methods utilizing induction heating have been recognized for some time, and induction heating is common in a wide variety of alloy systems. Its use for high melting point reactive alloys has been achieved on a commercial scale. U.S. Pat. No. 3,775,091 (Kreiz et al.) Describes a method for induction melting and forming titanium and other reactive metals and alloys. The method of Kraiz et al. Uses a water-cooled copper crucible located inside the induction coil. The crucible is longitudinally torn by at least one slit to reduce the damping or shielding effect caused by the electrically continuous crucible. The metal to be melted is charged into a crucible with a certain amount of slag material. Induction power is applied to heat the metal charge. As heating progresses, the slag melts and solidifies between the cold crucible wall and the hot metal, providing both thermal and electrical insulation between the crucible and the hot metal. Eventually, the initial charge melts to form a solid skull on the crucible wall and a molten pool is formed within the skull. The crucible can then be tilted to pour out the molten alloy, or the skull at the bottom can be continuously removed and cooled, thereby forming an integrally cast ingot of the same dimensions as the inner diameter of the crucible.

The method of Kraiz et al. Was improved by increasing the number of slits in the crucible, thereby eliminating the need for slag. This improved method allowed the melting of up to 75 pounds of titanium or 105 pounds of zirconium. Four
It is said that scale-ups from 00 to 500 pounds are possible, and the main constraint is the size of the power supply. DJ Chronister et al., "Induced Skull Melting of Titanium and Other Reactive Alloys", Journal of Metals, September 1986, 5
1-54. Although the method of Kreiz offers some advantages over the more common reactive metal melting method, it is an important requirement of a molten metal release system for rapid solidification methods, i.e., the need for small controlled molten metal flows. It is not aimed at.

Techniques and practices for the rapid solidification of reactive alloys, such as titanium alloys and titanium aluminides, are provided with means for forming and controlling large cold hearth melt rates and defined metal flows for rapid solidification by melt spinning. There is still a need for an improved processing system.

3. SUMMARY OF THE INVENTION The present invention provides an apparatus and method for rapidly solidifying reactive metals and their alloys in large batches (ie, batch sizes of 5 kg or more). Generally, the apparatus includes crucible means for holding a metal charge. The crucible means has side walls, a top and a bottom-including an orifice. The side walls, top and bottom define the interior of the crucible as an assembly. Some areas of the side walls and bottom are:
It is divided into at least two segments by a longitudinal slit. A portion of the nozzle means is located within the crucible means and extends through the orifice. The nozzle means includes a first end in communication with the interior. The second end of the nozzle means further includes a nozzle orifice for defining a flow of the molten alloy. Cooling means are provided for cooling the top, side walls and bottom of the crucible means. The apparatus further includes first inducing means for inducing an alternating current in the metal charge. Second inducing means is associated with it for inducing a current inside the nozzle means. The apparatus includes pressure control means for creating and maintaining a positive pressure inside the crucible, and quenching means including a rapidly moving cooling substrate. Positioning means positions the crucible and nozzle means relative to the quenching means. The crucible, the nozzle and the quenching means are housed in a sealing means for providing a positive or negative pressure controlled atmosphere therein.

The present invention further provides a method for melting and rapid solidification casting of an alloy, comprising: (a) crucible means having a side wall, a top and a bottom, the bottom including an orifice, A solid loading material comprising an alloy is placed inside the crucible means in which the top and bottom side walls define the interior of the crucible as an assembly and the side walls and bottom are divided into at least two parts by longitudinal slits over a portion of them. (B) melting the internal charge by inducing an alternating current therein; (c) continuously cooling the side walls and bottom of the crucible to remove a solid alloy layer from the molten charge to them. Contact and form,
And holding, thereby preventing contact of the molten metal with the side walls and bottom of the crucible; (d) nozzle means partially disposed within the crucible means and extending through the orifice, wherein the nozzle means Heating the nozzle means, including a first end in communication and a second end via a passage in the nozzle, the second end including a nozzle orifice to melt a portion of the layer adjacent the first end, the passage being (E) pressurizing the interior to create and maintain a positive pressure therein, causing the molten charge to flow at a controlled flow rate through the nozzle orifice; and (f) flowing the molten charge through the nozzle orifice; The molten charge is rapidly solidified by directing the flow formed by the flow of the molten charge through the nozzle orifice into contact with the rapidly moving cooling substrate.

The method and apparatus of the present invention have the advantage of melting reactive metals and their alloys in a cold wall crucible to minimize contamination due to melt / crucible reactions. In addition, for rapid solidification, means are provided for forming and directing the metal stream in a controlled manner onto a rapidly moving water-cooled substrate. This device is capable of producing rapidly solidified materials in larger batches that are currently being produced, and rapidly solidifies reactive metals in an efficient and reliable manner.

The metal filaments or ribbons produced by this method are suitable for use as a foil as cast or in an annealed state, or are finely ground and agglomerated into bulk articles by conventional powder metallurgy techniques. Can be made into powder.

4. BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be more fully understood with reference to the following detailed description of preferred embodiments of the invention and the accompanying drawings, in which:
Other advantages will become apparent: FIG. 1 shows a schematic view of the device of the invention located in an enclosing chamber containing a water-cooled casting wheel for producing rapidly solidified ribbons; FIG. 1 shows a longitudinal section of the crucible and nozzle assembly used in the apparatus of FIG. 1 and shows the details and relationships of the structure of the casting crucible and the nozzle; FIG. 3 shows the bottom of the crucible and shows details of the structure; FIG. 4 shows a detailed sectional view of the crucible and nozzle, showing the shape of the metal charge during the operation of the apparatus after melting but before the start of casting; FIG. 5 shows details of the crucible and nozzle. FIG. 2 shows a schematic cross-sectional view, showing the shape of the metal charge during operation of the apparatus after the start of casting.

5. DETAILED DESCRIPTION OF THE INVENTION AND PREFERRED EMBODIMENTS FIGS. 1 to 5 of the drawings show a preferred form of an apparatus for melting and rapidly solidifying and casting a reactive alloy in a controlled atmosphere or vacuum.

In summary, the device shown schematically at 100 includes a crucible means shown schematically at 2 for holding a metal charge. The crucible means 2 has a side wall 3, a top 7, and a bottom 20 containing the orifice 5. The side wall 3, the top 7 and the bottom define the interior 22 of the crucible as an assembly. The area of the side wall 3 and part of the bottom 20 is divided by the longitudinal slit 11 into at least two segments. Nozzle means 8
Are partially disposed in the crucible means 2 and extend through the orifice 5. Nozzle means 8 includes a first end 24 in communication with interior 22. The second end 26 of the nozzle means further comprises a nozzle orifice for defining the flow 6 of the molten alloy.
Including 28. Top 7, side walls 3 and bottom 20 of crucible means 2
Is provided with cooling means 4 for cooling. Device 10
0 further comprises first inducing means 30 for inducing an alternating current in the metal charge. Second inducing means 32 is associated with it for inducing a current in the nozzle means 8. Device 10
0 further comprises pressure control means 34 for creating and maintaining a positive pressure in the interior 22 of the crucible 2 and quenching means 36 comprising a rapidly moving cooling base. Positioning means 10
Position the crucible and the nozzle means with respect to the quenching means 36. The crucible, the nozzle means and the quenching means are housed in a sealing means 1 for applying a positive or negative pressure controlled atmosphere inside.

More particularly, FIG. 1 shows a housing or chamber 1 configured in a gas-tight manner. The chamber 1 contains a crucible 2, a nozzle 8, and a casting substrate 36. The crucible 2 is preferably a metal having high thermal conductivity,
For example, it is made of copper. The crucible 2 includes a slit 11 in part of the side wall 3 and in the bottom 20 to reduce the damping or shielding effect caused by the electrically continuous crucible. Cooling means 4 for supplying cooling water to the crucible 2 is provided. For this purpose, a water manifold which is an integral part of the crucible 2 is preferable. The induction coil 30 is located at the bottom of the crucible, around the working part, and is connected to a normal induction power supply (not shown) and a cooling water source (not shown).

The top of the crucible 2 is capped with a cap 7, which is preferably made of a metal with high thermal and electrical conductivity, for example copper or a copper-containing alloy. The cap is removable to allow access to the interior 22 of the crucible 2, but may hermetically seal the crucible. The cap 7 is connected to a cooling water source and includes a connection 34 through which an inert gas can be introduced to maintain a relative pressure difference between the crucible interior and the chamber environment.

Below the crucible 2 is located a casting nozzle 8 composed of a refractory material, for example a ceramic or a refractory metal, preferably tungsten or molybdenum. The nozzle 8, which is preferably cylindrical in shape and has an outer diameter smaller than the inner diameter of the crucible 2, is open in the upper part 24 and is arranged in the hole 5 in the bottom of the crucible 2, so that the upper part 24 of the nozzle is Open to the interior 22. The bottom 26 of the nozzle 8 is closed except for the small orifice 32. An induction coil 30 is connected to a conventional induction power supply, with the nozzle 8 located coaxially and separate from that of the crucible 2, and a cooling water source.

The crucible and nozzle assembly is supported by a frame 10 that can adjust the position of the assembly relative to the rapidly moving casting substrate 36. The casting substrate 36 is preferably a water-cooled wheel composed of a material having a high thermal conductivity, for example, copper or one of its alloys, and has a surface speed of 2500-7500 ft / min (about 762-2286 m / min). Driven to achieve.

FIG. 2 shows a longitudinal sectional view of the assembly of the crucible and the nozzle, and shows details and relationships of the structure of the nozzle 8 and the crucible 2. The bottom 20 and the side wall 3 of the crucible are divided into segments by slits 11 extending to about two thirds of the side wall 3. The metal is melted and held only in the lower part of the crucible 2 and the slit 11 must extend upward long enough to insulate the individual segments in this area. Internal passages 38 for cooling water in each segment
Is provided. Cooling water is supplied to the internal passage 38 through the manifold 4 which is an integral part of the crucible 2. The crucible 2 is fitted into a cylinder 40 made of a cast heat-resistant material, which reduces the possibility of deformation of the crucible 2 by the slit 11 and has a function of sealing the slit 11, thereby enabling the crucible 2 to be pressurized. I do. The crucible assembly is mounted on an insulating plate 42, which is
Is disposed on the holding bracket 44 connected to the.

The nozzle 8 is placed in the orifice 5 at the bottom of the crucible 2, open to the interior 22 of the crucible. Nozzle 8
Are insulated and insulated from the crucible 2 by a series of insulating and clamping rings 46, which are at the bottom of the crucible.
It is configured so that the position of the nozzle 8 with respect to 20 can be adjusted. Nozzle 8 and clamping ring assembly 46
Is a retaining plate bolted to the retaining bracket 44
Secured in place by 48.

FIG. 3 is a bottom view of the crucible and shows details of segment division. The side wall 3 of the crucible is divided into segments by longitudinal slits 11. The illustrated configuration has 24 segments. The bottom 20 of the crucible is divided into half the segments of the side wall by a radial slit 50 extending to the vicinity of the orifice 5 at the center of the bottom 20 and is made of unsegmented material to give the crucible 2 structural stability. A thin ring 52 is left. The bottom slit 50 is formed by alternately extending the side wall slits 11. The cooling water passages 38 are arranged such that the pair of side wall segments and bottom segment to which they connect are cooled by separate cooling loops.

To begin the melting and rapid solidification operations, the starting materials--either a single prealloyed ingot or a master alloy containing elemental alloying additives--are added to the crucible 2. Charge and seal cap 7 on top of crucible. Next, electric power is applied to the induction coil 30 of the crucible to heat the charged material. As the heating proceeds, the filler material begins to melt. The molten metal in contact with the crucible solidifies, thus forming and holding a layer of skull 54 of solid alloy facing the crucible wall 3 and bottom 20.
After heating and melting to form the molten metal pool 56 and the skull 54, the shape of the metal loading material before the start of casting is shown in FIG. Levitating force induced by an electric field
force) deforms the molten metal pool 56 to the general shape shown. The solid alloy skull 54 remains in the crucible and seals the opening at the upper end 24 of the nozzle 8.

In order to start the casting operation shown in FIG.
And the assembly of nozzles 8 is positioned above the mobile casting substrate 36. Power to the induction coil 32 surrounding the nozzle 8 heats the nozzle 8 and begins to melt the solid skull 54 adjacent the upper end 24 of the nozzle 8, thereby causing the molten metal 56 to
, Passes through a passage 58 inside the nozzle, and exits through an orifice in the nozzle bottom 26. The metal stream 6 discharged from the nozzle 8 impinges on the mobile casting substrate 36, where it rapidly solidifies into thin filaments 60. An inert gas is supplied to the crucible 2 through the mouth 34 of the sealing cap 7 to provide a pressure sufficient to maintain a metal stream 6 suitable for forming the filament 60. The gas pressure is controlled during the casting operation to compensate for the drop in metal head pressure as the crucible empties.

The following examples-amounts by weight-are provided for a more complete understanding of the invention. The specific techniques, conventional conditions, and reported data set forth to illustrate the invention are exemplary and should not be construed as limiting the scope of the invention.

Example 1 The crucible shown in FIGS. 2 and 3 was constructed. The crucible has an inner diameter of 43/4 inches (12.65 cm) and an inner height of 121/2 inches (31.75 cm), and a diameter of 1 1/2 inches (3.75 cm) at the bottom.
81cm). A vertical slit was cut into the lower 71/2 inches (19.05 cm) of the crucible wall, dividing the crucible in that area into 24 segments. The bottom of the crucible is 1/2 inch (1.27c
The slit was cut into m), dividing the bottom into 12 segments. On the side walls and bottom, cooling water flows from the inlet manifold at the top of the crucible, descends 12 sidewall segments, flows into the bottom segment, exits from it, and rises the other 12 sidewall segments The passage was cut to return to the discharge manifold. The lower 7 1/2 inches (10.05 cm) of the crucible is 1/4 thick
It was embedded within an inch (0.635 cm) layer of castable heat resistant material.

It consists of 11 turns of copper tube and has a total height of 6 inches (15.24c
m) was placed coaxially around the bottom of the crucible. Power for induction heating and melting was provided by a 3 kHz, 135 kW solid state induction power supply. The crucible and coil were placed on a holding bracket and substrate assembly that could move horizontally and vertically within the vacuum chamber. A crucible was charged with a charge consisting of approximately 10 pounds of a 1 inch (2.54 cm) diameter titanium-6% aluminum-4% vanadium rod. A water-cooled brass cap including a joint for introducing argon gas into the crucible was placed on the top of the crucible, and was fastened by a clamp attached to a holding bracket.

Outer diameter 1 1/2 inch (3.81cm), inner diameter 1 inch (2.54c)
m) and a 11/2 inch (3.81 cm) total height tungsten nozzle was inserted into the orifice at the bottom of the crucible and secured in place by a series of clamping rings and retaining plates mounted below the crucible support plate. .

The charge was then heated by applying power to the induction coil. As the charge is heated and melted,
The melt contacted the wall or bottom of the flowing crucible and solidified to form a solid skull. By changing the heating rate and the applied power level, conditions were established in which the entire charge was melted and contained within the solid skull. However, in this state, the flow of the liquid metal through the nozzle was not started.

Example 2 The device described in Example 1 is similar to Example 1, but with a length of 3
Overall height 1 coaxial with the inch (7.62cm) nozzle
The improvement was achieved by adding a three-turn induction coil of 1/2 inch (3.81 cm). Power to the coil was provided by a 10 kHz, 10 kW solid state inductive power supply. The general procedure outlined in Example 1 was followed except that the crucible charge was heated and melted while power was applied to the nozzle induction coil. With proper adjustment of the melting rate and power level, the molten metal from the crucible flowed into the nozzle and flowed out of the orifice until the crucible was empty except for the skull at the bottom of the crucible.

Example 3 A rapid solidification test was performed using the equipment outlined in Example 1 and the method outlined in Examples 1 and 2. Charge about 10 pounds (4.53 kg) of prealloyed ingot containing about 65% titanium and 35% aluminum into the crucible,
Elemental vanadium making up about 1.75% of the total weight of the charge was added. The power level was adjusted to allow the charge to melt and the vanadium to dissolve without the melt flowing into the nozzle. The power level was then increased to allow the molten metal to flow into and through the nozzle.

Immediately after the nozzle flow was established, the crucible / nozzle assembly was moved to a casting wheel that had already been started. The stream of molten metal impinged on the wheel and solidified to form a thin ribbon, which separated from the wheel downstream of the point of impact.

This rapidly solidified ribbon is approximately 0.17 inches (0.43 inches) wide.
cm) and 0.002 inches (0.005 cm) thick. The composition is 35.0% aluminum, 1.74% vanadium and 6
Analyzed with 3.3% titanium.

Example 4 Using the apparatus of the present invention, two rapid solidification casting tests were performed according to the same general method outlined in Examples 1, 2 and 3. The charge used for these castings has a nominal composition of 61.2
% Titanium, 14.1% aluminum, 19.5% niobium, 3.2%
It consisted of a prealloyed ingot of vanadium and 2.0% molybdenum. The first time is 3.9 kg in 5.5 kg of charged material
And a second time, 1.5 kg of the 3.3 kg charge were cast, with the remainder of the charge remaining as a solid skull in the crucible. The ribbon was 0.002 inches (0.005 cm) thick.
The composition consisted of 13.9% Al, 19.4% Nb, 3.09% V and 1.9%
% Mo, the balance being titanium, the other being 13.8% Al, 19.2% N
b, 3.19% V and 1.87% Mo, the balance being titanium.
This demonstrates the reliability and reproducibility of the present invention.

Example 5 Ribbons made according to Examples 3 and 4 were inspected. Approximately, 700 ppm or less of O _2, 420 ppm or less of N _2, and a penetration impurity content of less C 200 ppm, ribbon about 0.003 inch thick (0.008 cm) was found to have significant ductility. Ductility is achieved by folding the ribbon without breaking it (be
nding) is possible.

Example 6 Prepared according to Example 4, 13.9% Al, 19.4% Nb, 3.09%
A ribbon having a composition of V, 1.90% Mo, and the balance of titanium was hammer-milled to prepare -35 mesh powder. This powder is 1 inch (2.54 cm) in diameter and 6 inches (15.2 in) long.
A 4 cm) cylindrical stainless steel can was charged, evacuated to a vacuum, and then sealed under vacuum. The cans were then hot isostatically pressed and the cans were removed, giving a completely dense article.

Although the present invention has been described in considerable detail, it is not necessary to adhere to these details, and various changes or modifications will be obvious to those skilled in the art, all of which are defined by the claims. It will be understood that it is within the scope.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor by Richard Lister, Jr., 07960, New Jersey, USA, Edgehill Ave. 2 (72) Inventor Roboski, Alexander New Jersey, USA 07974, New Providence, Del Wick Lane 16 (58) Field surveyed (Int. Cl. ⁷ , DB name) B22D 11/06

Claims (2)

(57) [Claims] 1. An apparatus for melting and rapidly solidifying and casting an alloy comprising: (a) a crucible means for holding a metal charge, comprising a side wall, a top and a bottom having an orifice;
A crucible means wherein the side walls, top and bottom define the interior of the crucible as an assembly and are divided into at least two segments by longitudinal slits over a portion of them: (b) a part disposed in the crucible means; Nozzle means extending through the orifice, the nozzle end including a first end in communication with the interior and a second end through the passage of the nozzle, the second end further defining a flow of molten alloy. (C) cooling means for cooling the side wall and bottom; (d) a first means for inducing an alternating current in the metal charge.
(E) second induction means for inducing a current in the nozzle; (f) pressure control means for generating and maintaining a positive pressure in the interior; (g) a rapidly moving cooling substrate. (H) positioning means for positioning the crucible and the nozzle means with respect to the quenching means; and (i) surrounding the crucible, the nozzle and the quenching means and having a controlled atmosphere of positive or negative pressure therein. Means for applying; a device comprising: 2. A method for melting and rapidly solidifying an alloy, comprising: (a) having a side wall, a top and a bottom, the bottom being a crucible means including an orifice, wherein the side wall, the top and the bottom are formed. Charging a solid charge of an alloy into the crucible means defining an interior of the crucible as an assembly, the side walls and the bottom of which are divided into at least two parts by longitudinal slits over a part of them; ( b) melting the internal charge by inducing an alternating current therein; (c) continuously cooling the side walls and bottom of the crucible to form a solid alloy layer from the molten charge in contact with them;
And holding, thereby preventing contact of the molten metal with the side walls and bottom of the crucible; (d) nozzle means partially disposed within the crucible means and extending through the orifice, wherein the nozzle means Heating the nozzle means, including a first end in communication and a second end via a passage in the nozzle, the second end including a nozzle orifice to melt a portion of the layer adjacent the first end, the passage being (E) pressurizing the interior to create and maintain a positive pressure therein, causing the molten charge to flow at a controlled flow rate through the nozzle orifice; and (f) flowing the molten charge through the nozzle orifice; Rapidly solidifying the molten charge by directing the flow formed by the flow of the molten charge through the nozzle orifice into contact with the rapidly moving cooling substrate; Method.