- 1 Preface
- 2 Paiste’s development and use of B20 alloy
- 3 Stage 1. Production process at the foundry and mill (Weiland works and Swissmetal):
- 4 Stage 2. Paiste's process at their production facility
- 5 The German production facility
- 6 B20 alloy
- 7 B15 (Paiste Signature Sound Alloy)
- 8 B8 (2002 Alloy)
- 9 NS12 Nickel Silver
- 10 MS63 Brass
- 11 The spin forming process
- 12 The Turkish way: individual ingot casting
- 13 Why is UFIP important and why are they different?
- 14 A word about "cast" vs. "sheet bronze" cymbals and Zildjian's marketing
- 15 Notes and references
Introduction: Paiste's cymbal production process
The purpose of this wiki page is to go in depth of how the different alloys are produced by Paiste’s supplier(s), past and present.
Paiste is a unique cymbal company in that their alloys are substantially different in quality and sound characteristics compared to the “Turkish way” of B20 alloy production. Specifically, this difference in sound quality and consistency is a result of the way the alloys are manufactured.
This page will also cover briefly other major cymbal companies and how their alloy is manufactured.
Paiste’s development and use of B20 alloy
Paiste does not have a foundry, they have traditionally used an outside supplier to provide all of their alloys with the first production stage completed: blanks are produced at the specified size and thickness and delivered to Paiste's two production facilities in Germany and Switzerland.
- The B20 “blanks” were originally supplied by Swissmetal from 1957 to 1994, they were originally called "Metallwerke Dornach AG".
- Metallwerke Dornach supplied B20 alloy for the Swiss mint, Swiss coins were made out of B20 bronze.
- In 1957, Robert Paiste founded the original Swiss workshop across the lake from where Metallwerke Dornach was located by accident (Paiste had not used B20 alloy up to that point), little did he know that they were the only foundry and mill that produced B20 bronze in all of Switzerland and possibly all of northern Europe!
- Robert Paiste worked with Swissmetal to develop a process of rolling B20 blanks thin enough to produce cymbals: Fritz Steger explains the sourcing and development of Paiste's B20 alloy.
- The Formula 602 and Sound creation lines were discontinued around 1994 because Swissmetal stopped making B20 blanks. It is understood that Swissmetal went through substantial financial difficulties during this time, it’s also assumed it wasn’t cost effective anymore as Paiste would have been a small volume customer. In addition, Paiste was promoting the "Signature" or B15 cymbals that were designed to replace both series, so Robert Paiste did not pursue a replacement supplier.
- "Weilandworks" in Vöhringen Germany now supply all of Paiste's alloys but specifically: they supply the B20 blanks for the “classic 602’s” and "Modern essentials 602’s". when first presented to Robert Paiste, he asked for some small changes (changes in processing temperature in order to reproduce the classic 602 sound)
- B20 and B15 are "two-phase" alloys: meaning some of the tin is not dissolved in the copper grains but exists between them, in its natural state it is very brittle, there is a large amount of work done to the material (reheating/recrystallisation) to get the material conditioned so it can be rolled to the correct thickness without it cracking.
Stage 1. Production process at the foundry and mill (Weiland works and Swissmetal):
- It believed that Paiste's material suppliers (Weiland works and Swissmetal) have used this production process for a long time, possibly as far back as 1957 when Swissmetal first starting supplying B20 blanks to the Swiss factory.
- Wielandworks has their continuous casting system in their plant in England.
Continuous strip or band casting process
Weilandworks uses the continuous strip or band casting process for producing B8, B15 (and most likely) B20 blanks it supplies to Paiste.
What is the difference between gravity/ingot casting and continuous casting?
In "ingot casting", individual molds are filled with molten bronze to produce "ingots" whereas in continuous casting, the molten alloy is solidified into a very long "semi finished" billet, and at the same time, cut into slabs or planks for subsequent hot or cold rolling in the finishing mills.
What is the advantage of continuous casting?
Continuous casting helps improve the quality of metal products by reducing impurities and variations in size and shape, this results in consistent and higher-quality products with fewer defects.
The continuous casting method offers a superior surface finish and virtually eliminates internal porosity and centerline shrinkage during cooling compared to ingot casting.
The majority of bronze castings are produced through the individual ingot casting process. However, there are clear deficiencies in the this choice when compared to continuous casting.
What are the disadvantages of continuous casting?
It isn't economical to use this method with special metal alloys in low volume and small quantities
In conclusion, continuous casting offers several advantages, including high productivity, consistent quality, and cost-effectiveness.
Second hot rolling stage and or cold rolling stage (B8):
At the mill, the desired thickness is created by hot rolling  (see bottom of page for notes) B20 and B15 in multiple passes from a thick plank into a long thin sheet slightly thicker than the thickness required by the heaviest cymbal.
The hot rolling process forms the desired crystalline structure (size and shape) that defines the sound of the cymbal and makes the material durable but pliable enough that it can be worked and hammered without cracking.
After being rolled out to approximate size and thickness, round blanks are cut to the specified size and delivered to Paiste.
- All of Paiste's B20 and B15 cymbal blanks use this process with the exception of the Masters, Twenty and Twenty Custom Collection series.
- Both B20 and B15 alloys are cut into slabs before hot rolling (B20) and cold rolling (B15) to reduce the thickness to the proper level.
- Wielandworks rolls the B15 alloy at their Birmingham England facility.
- B15 slabs have to be reheated (annealed) after several cold rolling passes, they then have the surface cracks ground off before final finishing, this results in a 40% loss of material!
- In a 2006 interview, Robert Paiste stated that his big regret in 1994 was when their original B20 supplier Swissmetal stopped production, Robert did not buy and remove the 2nd hot rolling stage and move it to a new facility where Paiste could finish rolling the B20 slabs themselves.
B8 alloy is very different compared to B20 and B15: it's softer, much more malleable, easier to work and doesn't require multiple heating cycles before each rolling stage in order to prepare it for hammering. It's a "single-phase" alloy and can be cold rolled into sheets (Cold rolling occurs with the metal below its recrystallization temperature, usually at room temperature. Cold rolling operation actually increases the strength via "strain hardening" up to 20%, it also improves the surface finish and holds tighter tolerances).
Stage 2. Paiste's process at their production facility
Paiste is the only company out of the major cymbals companies that uses the "manual machine hammering" technique to shape the curve or “bow” of all of their top line cymbals, they invented and have used the same process since 1952 (they got their first hammering machine in 1952). Up until 1986, all Paiste cymbals were manual machine hammering with the exception of the 101 series. An electro pneumatic hammer is operated manually by the cymbal-smith, he wears a mount with a spindle on his left knee that holds the cymbal, he uses his thigh to move the cymbal in and out from the hammer to position the blows, with his right foot he controls the power/depth of the hammer blows, with his hands he rotates the cymbal to evenly distribute the hammer marks. Paiste has been using this technique and the same type of machines since at least the mid 50’s or earlier.
The next step is fine tuning: a different cymbal-smith now hammers the cymbal by hand to fine tune the shape and checks the bow with a ruler and on a steel flat table to make sure the edges are straight, he also checks the cymbal against a “master” for hammer pattern and shape of the bow.
Each cymbal-smith has a “specification card” that travels with each model/size of cymbal, it tells him the exact weight, thickness and hammering pattern for that cymbal.
All Paiste's top line cymbals are lathed by hand, up until 1986 all Paiste cymbals were lathed by hand with the exception pf the 101
Lathing does two things: brings the cymbal down to the desired thickness and creates the lathing grooves which refines the sound and defines the character of that cymbal line.
The cymbal-smith checks the thickness of the cymbal with a micrometer during this process, the thickness must be no more or less than 0.01mm.
The edges are cleaned up and chamfered, a serial number is laser etched into the bottom. The cymbals then have their respective logo, model, size printed on them and a protective coating is applied (Paiste was the 1st. to do this with the 602 series in the 1960’s).
Each cymbal is tested against a finished “Klangmuster” ("sound sample") for consistency, if it does not pass the cymbal is rejected and scraped.
The German production facility
The German facility was founded and started production after WWII around 1947/48, in 1957 Robert Paiste moved to Nottwil Switzerland by himself and setup the Swiss factory.The German factory is the sole producer of gongs, and has been since opening. Historically, both factories made both levels of product except the German factory didn't make any B20 cymbals or Giant beats.
Many 2002's were made at the German factory in 70s and 80s, there is a notion among some drummers that the Swiss versions are better quality... they are not, some German versions are usually a little heavier and a little darker sounding. The German factory also "finished" a small number of 602s during the preserial days, there are also examples of German 602's from the mid 1970's as well.
The German factory made practically all the vintage Paiste lines: 2002 (up to 1986), Sound formula, 2000, 1000, 400, 200, Stambul '65, Stambul, 404, 505, Ludwig cymbals, Dixies, Supers, Stanoples, Zilkos, etc. They still make all the lower lines and "OEM" cymbals. American drummers are less familiar with German Paistes because the Swiss factory did most of the exporting, the German Paistes were meant for the German market and probably certain countries in central and eastern Europe.
It is believed that only the German factory has the spin forming machines so all the current lower lines are "started" there and finished in Nottwil for export.
Cymbal lines using this alloy past and present:
Current: Formula 602, Formula 602 modern essentials
Past: Super Formula 602, Sound creation, Seven Sound Set, Joe Morello Set.
When the B20 blanks reach the Paiste factory, they are reheated and then quenched in water to "anneal" them (soften), a bell can now be stamped in the blank, after cleaning, it's ready for hammering.
Once we reach this stage the production process (hammering/lathing) is virtually identical to all the other top line series regardless of alloy.
B15 (Paiste Signature Sound Alloy)
Cymbal lines using this alloy past and present:
Current: Signature, Signature Dark Energy, Signature Traditionals, Signature Precision, Signature Reflector.
Past: Visions, Sound formula.
Paiste's B15 (Signature Sound Alloy) were initially supplied by "Kovohutí Příbram" foundry/mill in the Czech republic, they had serious issues with cracking of the finished cymbals, Weilandworks resolved the issue and production was moved there permanently: Fritz Steger describes the early production issues with B15
B15 like B20, goes through some of the same processes: initially hot rolled then the last stages is cold rolled. Cold rolling alloy allows for greater consistency between blanks compared to traditional B20 cymbal alloy, and is more inline with Paiste's B8 production methods. When they reach the Paiste factory, B15 blanks are reheated to "anneal" them (soften) and then quenched in water. After this process, the blank is allowed to cool for 24 hours. As a result of annealing, the material is now more pliable, tougher and ready to have a bell pressed into the blank and ready for hammering. Once we reach this stage the production process (hammering/lathing) is virtually identical to all the other top line series regardless of alloy.
Early 90's factory tour with Nicko McBrain: B15 Signature cymbal production tour
U.S. patent for "Signature alloy"
Paiste's description of the production process in the U.S. patent:
"An alloy containing, for example, 14.7 percent by weight tin, 0.08 percent by weight phosphorus and 85.22 percent by weight copper is initially melted in an induction melting furnace.
The melt is delivered at a temperature of 1000° C. to 1200° C. into a heat retention or holding furnace of a strip or band casting installation. A strip or band is cast.
The cast strip or band has, for example, a width of 670 mm and a thickness of 18 mm. This strip or band cannot be coiled and is therefore cut into plates of approximately 3 to 4 meters length.
Such plates are now homogenized at 600° C. to 700° C. during about 10 to 25 hours.
Then the casting and oxidation skin is removed by means of a milling tool or cutter or equivalent structure.
Thereafter the plates are initially only slightly cold rolled, i.e. by about 20 percent and then recrystallized at temperatures between 500° C. and 700° C.
This process cycle of cold rolling and recrystallization takes place until a final sheet or plate thickness of 1 to 2 mm is obtained.
Then a final annealing is carried out at temperatures between 400° C. and 500° C.
The obtained grain size then should be between 0.003 and 0.015 mm. The hardness should lie between 150 250 kilopounds per square millimeter, depending on the strived for sound or tone character.
Now circular blanks or discs of, for example, 200 to 610 mm in diameter are cut out of this sheet or plate from which there is formed the aforedescribed cymbal."
B8 (2002 Alloy)
Cymbal lines using this alloy past and present:
Current: 2002, 2002 big beat, Giant Beat, Rude, 900, 900 colorsound, Pst 8, Pst 7, Pst 5, Pst X
Past: Dimensions, Innovations, 900 series marching/symphonic, 3000, 2000, 1000, Alpha, 505, 404, 802, 502, 201, Stambul, Stambul 65, Ludwig Standard, Ludwig Stanople, Dixie, Super and many more!
Robert Paiste had started to experiment with B8 alloy as early as 1963, he was looking for a better sounding replacement for the then currently used NS12 (Nickel silver) alloy. B8 is an industrial alloy used in bearings bushes and sleeves, it is readily available from many manufactures. Once the blanks arrive at Paiste, they would heat the center of the cymbal in order to press the in the bell.
For the china type cymbals they "spinform" the shape of the bell into the unique cylindrical shape.
NS12 Nickel Silver
Not currently used but the production process would be very similar to the B8 alloy.
Cymbal lines using this alloy past and present:
Past: 402 , Stambul , Zilko Standard, Arbiter Zilket, Standard, Ludwig Standard, Ludwig Stanople, Dixie, Super, 101.
Traditionally, Paiste gongs have been made from nickel silver since their inception in the early 1930's.
Nickel silver as used in cymbal making is an alloy of copper and nickel, and an alloy with about 12% nickel is used for some beginners' cymbals. A very few specialised high-quality cymbals are also made from nickel silver, as are some top-quality gongs tending to the more modern and exotic sounds. Nickel silver is malleable and available as commercial sheet metal, and gives a bright tone but without the shimmer and sensitivity of tin bronzes. In the early to mid 20th century nickel alloy cymbals were far more widely produced and used, and so many older recordings were probably made using cymbals with a significant nickel content.
The production process would be very similar to the B8 alloy.
Cymbal lines using this alloy past and present:
Current: 101 brass
Past: Zilko, 200, 101, 302, Brass tones
Brass cymbals are inexpensive beginners' cymbals Brass is easily worked, readily available as sheet metal, and easily the cheapest metal stock normally used for cymbals. The tone of brass cymbals tends to be warm but dull compared to any sort of tin bronze, and very few drummers exploit it.
The spin forming process
The Cymbal Book, By Hugo Pinksterboer: "Spin forming is a technique that has been used in various industries for decades. Roland Meinl was the first manufacturer who developed a specific spin forming machine for cymbals, in the mid-sixties. Before, this technique was performed by hand. In the first half of the twentieth century a variety of spinformed or "spun" cymbals were made in the USA, available under the names of Ludwig, Davitian and others. Premier has also made such cymbals."
Staring in 1978 with the 101 series, Paiste started using the "spin forming" process to shape their cymbals instead of hammering. In 1986 it is believed that several of the new lower lines (200, 400 and 1000) used this process and the majority of the lower lines since 1986 use the spin forming process, this would include: 802/plus, 502, 402, 302, 201 bronze, noise works, brass tones, OEM cymbals made for other manufacturers. It is believed that only the German factory has the spin forming machines, so all the lower lines would start there before being finished at the Swiss factory. Current lines most likely using this process: 900, 900 colorsound, Pst 8, Pst 7, Pst 5, Pst 3, 101 brass, Pst X.
What is the spin forming process?
Metal spinning, also known as spin forming most commonly, is a metalworking process by which a disc or tube of metal is rotated at high speed and formed into an axially symmetric part. Spinning can be performed by hand or by a CNC lathe. A pre-sized metal disk is then clamped against the block by a pressure pad, which is attached to the tail stock. The block and workpiece are then rotated together at high speeds. A localized force is then applied to the workpiece to cause it to flow over the block. The force is usually applied via various levered tools. The metal is formed into seamless asymmetric shapes by a combination of rotational motion and force. In this process a tube or a disc of metal is rotated at a high speed, and is then transformed into the desired axially symmetrical object. This process of metal spinning has similar techniques to clay pottery sculpting and can be performed using CNC, hydraulic power or by hand.
The Turkish way: individual ingot casting
The traditional Turkish cymbal production process involves pouring molten metal into a mold (looks like a small pot), which produces a single disc/puck that will reheated and rolled, rotated and rolled again multiple times, usually being reheated at each rolling stage finally producing a small "sheet" or blank, the bell is pressed, the blank is then hammered to achieve the proper shape and then lathed into a finished cymbal. This process is extremely labor-intensive and requires a high degree of skill from all hands involved in the production line.
Cymbal lines using this alloy past and present:
Past: Twenty, Twenty Custom Collection
Twenty and Twenty Masters Collection production
The original “Twenty” blanks were supplied from the Foundry of Murat Diril in Turkey along with pre-work done to the cymbals before they were shipped off to Switzerland for completion.
There were well publicized issues with the quality of the blanks and high rejection rate, so Turkish suppliers were changed before the current Twenty Custom/Twenty Masters series started.
The process with their new supplier according to Paiste: "They begin by being hammered and shaped in Turkey, then we send them to Switzerland where we do the finish hammering and lathing and all the other work that makes it a Paiste cymbal."
All the hammering is done by hand according to Erik Paiste: “Paiste emphasizes that every crucial stage of the production is completed by hand, from the initial casting to the lathing and hammering.”
"Boutique" cymbal makers
The majority of "boutique" cymbal makers use Turkish blanks made with the traditional "individual ingot casting" process.
These may include: Paul Francis/Cymbal Craftsman, Matt Nolan, Craig Lauritsen, Ray Byrne, Funch, Justin Ottaviano, Nicky moon, Tim Roberts and Marius Buck.
Roberto Spizzichino made handmade cymbals in Tuscany from 1980 to 2011, he formally left UFIP in 1986. His early cymbals were ink-stamped “Spizz”. He used B20 bronze; both Chinese and Turkish Alloy cymbals are out there, in several distinct cymbal styles. Mainly jazz rides. Roberto died on November 22, 2011 at 67 years old.
Michael Paiste is the son of Robert Paiste.
Michael is an individual cymbal maker producing custom cymbal from Turkish blanks, he also modifies cymbals to the customers specifications. It is believed Michael mainly does this as a hobby and not as a full-time occupation. Michael is widely respected as one of the finest cymbal makers there is. He has definitely inherited all of his father's experience and knowledge.
Why is UFIP important and why are they different?
UFIP is the second oldest cymbal company (est. 1931) to produce cymbals from B20 bronze.
They are unique because they come from the Italian culture of church bell making or “bronze casters” as they call themselves. They use traditional techniques that have been practiced for several hundred if not a thousand years on casting bronze church bells.
Originally, their cymbals were gravity cast, at some point we believe possibly in the mid-1970s, UFIP developed the “rotocasting” technique where molten bronze is poured into a spinning mold that is made in the shape of a cymbal: this includes the bell and the “bow” or curve of the cymbal.
This process produces a dense and consistent alloy without inclusions, porosity or defects. This process also creates a different sounding cymbal because it is not hot rolled or cold rolled at any point but it is hammered and lathed (most models).
For several decades, UFIP was the only other cymbal company (besides Paiste) to make their own gongs.
What is centrifugal casting and why is it better?
The process involves using a centrifugal force (high-speed rotation action) to exert pressure on the molten metal, and it is poured from an external source into a spinning die. The centrifugal force acts to distribute the molten metal in the spinning die at pressures close to 100 times the force of gravity. The mold rotates until the whole casting solidifies. Because of the high G-forces involved in this casting method, the less dense materials, including impurities, are forced to go to the inside diameter periphery of the part, which is subsequently removed by machining, and defects related to gas and porosity are reduced.
A word about "cast" vs. "sheet bronze" cymbals and Zildjian's marketing
All top line and mid level cymbals are cast bronze, only entry level/beginner cymbals are made from brass but they are still "cast"!
There is much confusion (due to marketing spin) over "individually cast" cymbals vs. "sheet bronze" cymbals. In the early 1980s, Zildjian started the fray of "individual casting" by marketing each of their cymbals is cast into to a disc from molten bronze. From there each disc is shaped into a unique cymbal. What wasn't said (but clearly implied) is that anything that's not individually cast (Paiste) is somehow born of inferior quality. This is a misleading way to divert discussion away from the wide variability within Zildjian's products AND the fact that they have been using a press to stamp the shape of their cymbals since the 1970's.
The simple fact is that all cymbals, whether they are B8, B10, B12, B15 or B20 are cast bronze with "bronze" defined as an alloy of copper and tin. That bronze may be cast in individual pots or "continuously cast" (like a conveyor belt). It doesn't matter, the result of Paiste's supplier casting large planks of bronze vs. casting in individual pots is that they achieve a high level of consistency within and among their cymbal lines.
Regarding comparing both alloys (B8 vs B20) to one another; they have different copper/tin ratios, they have different physical and sonorous qualities. Neither is better or worse, just different, and any metallurgist will tell you that a true apples-to-apples comparison would be to compare the B20 from "Company X" vs. the B20 from "Company Y" because "proprietary secrets" of cymbal alloys are not their ingredients, but how the ingredients are prepared. Factors such as melting temperatures/rates, holding temperatures, cooling temps/rates, tempering methods, annealing methods, rolling methods, etc. play HUGE roles in formulating the cymbal sound long before the first shear, hammer, cup press, and lathe ever touch it.
B8 does get a bum rap for a number of reasons: B8 takes well to continuous casting into a sheet because it is more malleable than B20 and doesn't need to be hot rolled. Its inherent malleability allows more automated processes to replace individual rolling of ingots into small sheets or blanks. As a result of this process, Zildjian and Sabian "stamp out" thousands of B8 cymbals and market them as "beginner" or "student" lines degrading the status of this alloy. The workmanship on these cymbals is minimal (with few exceptions from Sabian) and their sound reflects that. Thus their marketing of "low-line B8 sheet cymbals" vs. the "flagship B20 cast cymbals" perpetuates this misconception. If you look at a B8 cymbal from Zildjian and Sabian vs. a B8 cymbal from Paiste, there's really no comparison!
Paiste pioneered the use B8 for cymbals in 1963 and put extensive workmanship into their cymbals, especially the professional-grade models. These instruments certainly hold their own among the legends of rock and even jazz. B8 offers more top end clarity than B20, and Paiste has developed and harnessed this alloy for enhanced warmth and low-end than previously thought. Furthermore, since B8 is inherently "brighter" than B20, cymbals can be made thinner enhancing their dynamic response & range while maintaining cut.
B20 cymbals tend to be more expensive because processing the alloy requires extensive multi-directional hot rolling. If this is not done properly and at the proper temperatures, then tin will be irregularly distributed throughout the blank resulting in brittle lines or "canyons". B20 has a broader low-end spread which is preferred by jazz guys who want to "blend". In loud rock n' roll, much of this lower and mid-frequency spread is drowned out, meaning the only way to cut through is to make the cymbal thicker. One exception to this rule is the A-Custom line which was introduced by Zildjian to compete with Paiste's shimmering clarity. Another exception is Sabian's AAX line, these cymbals do have nice clarity and spread. Point being that while Paiste has enhanced their B8 offerings to sound like B20, Zildjian and Sabian have been working their B20 offerings to sound like B8.
Although Zildjian strongly markets the "individual casting" of their B20 cymbals, they probably don't spend much time telling people that the deep hammer pocks on their expensive K Constantinople line are made by machines capable of hammering pressures 4x-greater than the human arm, they also don't focus on the fact that virtually all of their cymbals are stamped into shape instead of hammering them to shape them. Many of their processes are automated and that's not a bad thing but rather it's only as "good" or "bad" in terms of how the marketing people choose to spin it.
The two ads below on the left were produced before Sabian existed and Meinl was minor player and had not entered the U.S. market ('79- '82), Paiste was Zildjian's only real competition at the time.
Notes and references
 Rolling is a metal forming process in which metal stock is passed through one or more pairs of rolls to reduce the thickness, to make the thickness uniform, and/or to impart a desired mechanical property.
The concept is similar to the rolling of dough. Rolling is classified according to the temperature of the metal rolled:
- If the temperature of the metal is above its recrystallization temperature, then the process is known as hot rolling.
- If the temperature of the metal is below its recrystallization temperature, the process is known as cold rolling.
 Cross rolling is a way of reducing the directional dependency of different properties of the rolled plate.
Cross rolling is normally done by changing the rolling direction by 90° about the normal direction.
Changes in residual stress distribution cross rolling leads to rolled product of comparatively uniform mechanical properties in all directions.
 Annealing is a heat treatment that alters the physical and sometimes chemical properties of a material to increase its ductility and reduce its hardness and makes it more workable.
It involves heating a material above its recrystallization temperature, maintaining a suitable temperature for an appropriate amount of time and then cooled.
Bronze can be either cooled slowly in air, or quickly by quenching in water. In this fashion, the metal is softened and prepared for further work such as hammering, shaping, stamping, or forming.
 Tempering is a process of heat treating, it is done to reduce some of the excess hardness, and is done by heating the metal to some temperature below the critical point for a certain period of time, then allowing it to cool in still air.
The exact temperature determines the amount of hardness removed, and depends on both the specific composition of the alloy and on the desired properties in the finished product.