Austenitic stainless 304L / 316L / 316LN ESR

Brazing

Sourced pairings

Preparation

• Mo-Mn then Ni plating
• none
• none mentioned
• not stated
• every brazed stainless surface is copper-electroplated before the brazing cycle

Compatibility

What documents state about this material faced with a filler metal, without the other member of the joint. A statement that names the exact filler comes first. A statement about a whole AWS class comes after it: a class covers dozens of alloys, so it is the weaker of the two, and the corpus never turns one into the other. Last come statements about a pair of base metals that name no filler at all. They are the weakest of the three, and they do not contradict the two above: a table that cannot generalize about a pair can still list a filler class for each metal of that pair separately. The three levels answer three different questions.

• does not wetBCu-1
  The Bendix report states that none of the braze alloys wetted the unplated stainless steel specimens when they were brazed in the dry hydrogen atmosphere, because the hydrogen atmosphere was not adequate to keep the stainless steel from oxidizing.
  Conditions and source

  Wetting evaluation section, on coupons and not on a joint. The specimens are UNPLATED and the atmosphere is DRY HYDROGEN, and the report names the cause, hydrogen being unable to keep the chromium of the steel from oxidizing. Pure copper is NOT among the five alloys the report selects after plating, so this entry has no plated counterpart in the same document, unlike the three silver and gold alloys projected alongside it. One further reserve: the report brazes at 55 C above each alloy's liquidus, which for pure copper is 1138 C, a temperature at which the comparison with the low-melting silver alloys of the same table is not a comparison of equals.

  [A]W. G. Gates and G. E. Parkhurst, The Bendix Corporation, Kansas City Division, Ceramic-to-Metal Sealing, BDX-613-1683 (Rev.), final report PDO 6989258, published March 1977, USERDA contract EY-76-C-04-0613

• does not wetCusil
  The Bendix report states that none of the braze alloys wetted the unplated stainless steel specimens when they were brazed in the dry hydrogen atmosphere, because the hydrogen atmosphere was not adequate to keep the stainless steel from oxidizing.
  Conditions and source

  Wetting evaluation section, on coupons and not on a joint. THE CONDITION IS THE WHOLE POINT AND IT IS IN THE SENTENCE: the specimens are UNPLATED and the atmosphere is DRY HYDROGEN, and the report names the cause, hydrogen being unable to keep the chromium of the steel from oxidizing. On the same coupons with an 8 micrometre nickel plating, electrolytic from a nickel-chloride solution or electroless nickel-boron, five of the twelve alloys wet acceptably, Nicusil 3, Lithobraze 725, Palcusil 10, Nicoro 80 and 80-20, and Nicusil 3 is judged the best. THREE further reserves. ONE, the printed grade: the body of the report writes 304 Stainless Steel coupons while the caption of figure 2 writes 304L Stainless Steel Wetting Coupons, and 304L is one of the three grades the Matter card of this key names. TWO, nothing here is stated about 316L or 316LN. THREE, this corpus carries a production pairing on the same key with the same alloy, copper-ofe--stainless-316l--pwt-linac, where every brazed stainless surface is copper-electroplated before the cycle and the joints leak-check at 5e-10 mbar l/s. A bare surface in dry hydrogen and a plated surface in vacuum are two different questions, and the corpus answers both rather than averaging them.

  [A]W. G. Gates and G. E. Parkhurst, The Bendix Corporation, Kansas City Division, Ceramic-to-Metal Sealing, BDX-613-1683 (Rev.), final report PDO 6989258, published March 1977, USERDA contract EY-76-C-04-0613

• does not wetIncusil 10
  The SRNL sessile drop study states a complete lack of wetting and absolutely no interaction between Incusil and 304L stainless steel, the braze melting into a small ball that rolled off the surface.
  Conditions and source

  Sessile drop, not a joint. Five braze alloys in 0.020 inch wire on three substrates, 304L stainless steel, Ni 200 and Pd-25Ag, in a vacuum furnace evacuated to at least 8e-4 Torr, ramped 10 C per minute to 25 C below the solidus, held 10 minutes, then 20 C per minute to the brazing temperature and held 10 minutes. The Incusil of the study is printed as Ag 63, Cu 27, In 10, which is exactly the composition this corpus carries under ag-cu-in-incusil-10, with a printed solidus of 605 C and liquidus of 725 C and trials at 750, 775 and 800 C. Four of the five alloys wetted all three substrates and only this combination failed. FOUR reserves. ONE, the result was VERIFIED: additional tests were conducted with more aggressive cleaning to verify the lack of wetting, and those samples also balled up, which is why this is written as a constat and not as a suspicion. TWO, the printed substrate is 304L, one of the three grades the Matter card of this key names, Austenitic stainless 304L / 316L / 316LN ESR, and nothing here is stated about 316L or about 316LN. THREE, a drop posed on a coupon is not a brazed joint: there is no object, no geometry and no capillary gap, and the corpus records this as a wetting fact and not as a pairing. FOUR, this corpus carries a pairing where the same steel key is brazed successfully in production, copper-ofe--stainless-316l--pwt-linac, with a silver-copper eutectic and every brazed stainless surface copper-electroplated first. Different filler, prepared surface: the two do not contradict each other, and reading either one alone would lose what the other says about preparation.

  [A]P. Korinko, L. Angelette, A. MacMurray, Savannah River National Laboratory, M. Golyski, Savannah River Nuclear Solutions, P. Kuzbary, Clemson University, Evaluation of Braze Joints for Hydrogen Purification Diffuser, SRNL-STI-2021-00334 R1, July 2021, for the proceedings of the International Brazing and Soldering Conference, Denver, 3 to 6 October 2021

• does not wetNicoro-80
  The Bendix report states that none of the braze alloys wetted the unplated stainless steel specimens when they were brazed in the dry hydrogen atmosphere, because the hydrogen atmosphere was not adequate to keep the stainless steel from oxidizing.
  Conditions and source

  Wetting evaluation section, on coupons and not on a joint. The specimens are UNPLATED and the atmosphere is DRY HYDROGEN, and the report names the cause, hydrogen being unable to keep the chromium of the steel from oxidizing. On the SAME coupons with nickel plating, Nicoro 80 is one of the five alloys that wet acceptably on both types of plating. One further reserve, and it matters for how far this entry travels: on metallized alumina the same report finds Nicoro 80 among the alloys that gave gross vacuum leaks and lower tensile strength through braze alloy penetration, which is a different substrate and a different mechanism.

  [A]W. G. Gates and G. E. Parkhurst, The Bendix Corporation, Kansas City Division, Ceramic-to-Metal Sealing, BDX-613-1683 (Rev.), final report PDO 6989258, published March 1977, USERDA contract EY-76-C-04-0613

• wetsNioro
  Kohl states that this filler will wet tungsten and molybdenum as well as copper, Kovar, nickel and stainless steel, with excellent flow.
  Conditions and source

  Book page 192, table XVI, Brazing filler metals for high-vacuum systems. The table carries its own reserve, printed under it: adapted from the list of a commercial manufacturer, so it relays a manufacturer selection list and not a measurement by the author. The Applications column names base metals and never names the other member of the joint. Row 13 of the table, composition Ni 18 and Au 82, which matches the corpus entry Nioro BAu-4 exactly. The table says stainless steel without a grade. The corpus carries 316L under stainless-316l, and Kohl elsewhere in the same paper writes 18-8 stainless steel, so the entry is narrower than the sentence it records.

  [A]W. H. Kohl, Soldering and brazing, Vacuum, volume 14, number 5, pages 175 to 198, 1964, Pergamon Press, PII 0042-207X(64)90858-9

  Peer-reviewed review article on soldering and brazing for vacuum devices, republished later in the Handbook of Vacuum Physics edited by A. H. Beck. Table XVI, Brazing filler metals for high-vacuum systems, book page 192, lists 21 filler metals with liquidus, solidus and an Applications column. The table carries its own reserve, printed under it: adapted from the list of a commercial manufacturer. It is therefore a manufacturer selection list relayed by the author, not a measurement of his own, and the Applications column names base metals without naming a partner. The page of each statement is carried by the entry that uses it, never by this registry line.

• does not wetPalcusil 10
  The Bendix report states that none of the braze alloys wetted the unplated stainless steel specimens when they were brazed in the dry hydrogen atmosphere, because the hydrogen atmosphere was not adequate to keep the stainless steel from oxidizing.
  Conditions and source

  Wetting evaluation section, on coupons and not on a joint. The specimens are UNPLATED and the atmosphere is DRY HYDROGEN, and the report names the cause, hydrogen being unable to keep the chromium of the steel from oxidizing. On the SAME coupons with nickel plating, Palcusil 10 is one of the five alloys that wet acceptably on both types of plating, and it went forward to the tensile comparison. Two further reserves. ONE, the printed grade: the body writes 304 Stainless Steel while the caption of figure 2, which happens to show Palcusil 10 coupons, writes 304L Stainless Steel Wetting Coupons. TWO, on metallized alumina rather than on steel, the same report finds that Palcusil 10 gave gross vacuum leaks and lower tensile strength through braze alloy penetration of the metallization when held 10 minutes at 55 C above its liquidus, which is a different failure on a different substrate and is recorded with the pairing alumina--kovar--nicusil-3 rather than here.

  [A]W. G. Gates and G. E. Parkhurst, The Bendix Corporation, Kansas City Division, Ceramic-to-Metal Sealing, BDX-613-1683 (Rev.), final report PDO 6989258, published March 1977, USERDA contract EY-76-C-04-0613

• listedAWS class BAg
  The AWS combination table lists the BAg class for brazing this base metal to Cu and Cu alloys, carbon and low-alloy steels, cast iron, stainless steel, Ni and Ni alloys, Ti and Ti alloys, Be, Zr, V and alloys, reactive metals, W, Mo, Ta, Nb and alloys, refractory metals, tool steels.
  Conditions and source

  Book page 75, chapter 3, table 3.2, Base Metal-Brazing Filler Metal Combinations. The cells that carry this class for this base metal name these partners: Cu and Cu alloys, carbon and low-alloy steels, cast iron, stainless steel, Ni and Ni alloys, Ti and Ti alloys, Be, Zr, V and alloys, reactive metals, W, Mo, Ta, Nb and alloys, refractory metals, tool steels. A partner is what the cell pairs the base metal with, it does not index this entry. The table lists classes, it does not qualify them, and an empty cell is never a prohibition. The class is written as the document writes it, BAl-Si becoming BAlSi here, and it is never mapped to any grade of the corpus. The dagger printed by the document on this cell reads: special brazing filler metals are available and used successfully for specific metal combinations. The asterisk printed by the document on this cell reads: refer to the text for information and appropriate individual chapters on the specific compositions within each classification. The table names stainless steel without a grade. The corpus carries 316L under stainless-316l, so the entry is narrower than the cell it records.

  [A]AWS Brazing Handbook, American Welding Society, chapter 3 Brazing Filler Metals and chapter 33 Electron Tubes and Vacuum Equipment

  Handbook of the American Welding Society. Three tables are read by the corpus. Table 3.2 page 75, Base Metal-Brazing Filler Metal Combinations, a two-entry matrix of base metal families whose cells carry AWS filler classes. Table 3.3 page 76, Maximum Service Temperatures Recommended for Various Brazing Filler Metal Compositions, one continuous and one short-term temperature per class. Table 33.1 page 585, Composition of Brazing Filler Metals Specially Produced for the Brazing of Vacuum Devices and Equipment, with liquidus and solidus in Fahrenheit and Celsius. The chapter, the table and the page of each statement are carried by the entry that uses it, never by this registry line.

• listedAWS class BAlSi
  The AWS combination table lists the BAlSi class for brazing this base metal to Al and Al alloys.
  Conditions and source

  Book page 75, chapter 3, table 3.2, Base Metal-Brazing Filler Metal Combinations. The cells that carry this class for this base metal name these partners: Al and Al alloys. A partner is what the cell pairs the base metal with, it does not index this entry. The table lists classes, it does not qualify them, and an empty cell is never a prohibition. The class is written as the document writes it, BAl-Si becoming BAlSi here, and it is never mapped to any grade of the corpus. The number sign printed by the document on this cell reads: recommended only if the nonaluminum alloy is nickel plated first. The table names stainless steel without a grade. The corpus carries 316L under stainless-316l, so the entry is narrower than the cell it records.

  [A]AWS Brazing Handbook, American Welding Society, chapter 3 Brazing Filler Metals and chapter 33 Electron Tubes and Vacuum Equipment

  Handbook of the American Welding Society. Three tables are read by the corpus. Table 3.2 page 75, Base Metal-Brazing Filler Metal Combinations, a two-entry matrix of base metal families whose cells carry AWS filler classes. Table 3.3 page 76, Maximum Service Temperatures Recommended for Various Brazing Filler Metal Compositions, one continuous and one short-term temperature per class. Table 33.1 page 585, Composition of Brazing Filler Metals Specially Produced for the Brazing of Vacuum Devices and Equipment, with liquidus and solidus in Fahrenheit and Celsius. The chapter, the table and the page of each statement are carried by the entry that uses it, never by this registry line.

• listedAWS class BAu
  The AWS combination table lists the BAu class for brazing this base metal to Cu and Cu alloys, carbon and low-alloy steels, cast iron, stainless steel, Ni and Ni alloys, W, Mo, Ta, Nb and alloys, refractory metals, tool steels.
  Conditions and source

  Book page 75, chapter 3, table 3.2, Base Metal-Brazing Filler Metal Combinations. The cells that carry this class for this base metal name these partners: Cu and Cu alloys, carbon and low-alloy steels, cast iron, stainless steel, Ni and Ni alloys, W, Mo, Ta, Nb and alloys, refractory metals, tool steels. A partner is what the cell pairs the base metal with, it does not index this entry. The table lists classes, it does not qualify them, and an empty cell is never a prohibition. The class is written as the document writes it, BAl-Si becoming BAlSi here, and it is never mapped to any grade of the corpus. The table names stainless steel without a grade. The corpus carries 316L under stainless-316l, so the entry is narrower than the cell it records.

  [A]AWS Brazing Handbook, American Welding Society, chapter 3 Brazing Filler Metals and chapter 33 Electron Tubes and Vacuum Equipment

  Handbook of the American Welding Society. Three tables are read by the corpus. Table 3.2 page 75, Base Metal-Brazing Filler Metal Combinations, a two-entry matrix of base metal families whose cells carry AWS filler classes. Table 3.3 page 76, Maximum Service Temperatures Recommended for Various Brazing Filler Metal Compositions, one continuous and one short-term temperature per class. Table 33.1 page 585, Composition of Brazing Filler Metals Specially Produced for the Brazing of Vacuum Devices and Equipment, with liquidus and solidus in Fahrenheit and Celsius. The chapter, the table and the page of each statement are carried by the entry that uses it, never by this registry line.

• listedAWS class BCu
  The AWS combination table lists the BCu class for brazing this base metal to carbon and low-alloy steels, cast iron, stainless steel, Ni and Ni alloys, W, Mo, Ta, Nb and alloys, refractory metals, tool steels.
  Conditions and source

  Book page 75, chapter 3, table 3.2, Base Metal-Brazing Filler Metal Combinations. The cells that carry this class for this base metal name these partners: carbon and low-alloy steels, cast iron, stainless steel, Ni and Ni alloys, W, Mo, Ta, Nb and alloys, refractory metals, tool steels. A partner is what the cell pairs the base metal with, it does not index this entry. The table lists classes, it does not qualify them, and an empty cell is never a prohibition. The class is written as the document writes it, BAl-Si becoming BAlSi here, and it is never mapped to any grade of the corpus. The table names stainless steel without a grade. The corpus carries 316L under stainless-316l, so the entry is narrower than the cell it records.

  [A]AWS Brazing Handbook, American Welding Society, chapter 3 Brazing Filler Metals and chapter 33 Electron Tubes and Vacuum Equipment

  Handbook of the American Welding Society. Three tables are read by the corpus. Table 3.2 page 75, Base Metal-Brazing Filler Metal Combinations, a two-entry matrix of base metal families whose cells carry AWS filler classes. Table 3.3 page 76, Maximum Service Temperatures Recommended for Various Brazing Filler Metal Compositions, one continuous and one short-term temperature per class. Table 33.1 page 585, Composition of Brazing Filler Metals Specially Produced for the Brazing of Vacuum Devices and Equipment, with liquidus and solidus in Fahrenheit and Celsius. The chapter, the table and the page of each statement are carried by the entry that uses it, never by this registry line.

• listedAWS class BNi
  The AWS combination table lists the BNi class for brazing this base metal to Cu and Cu alloys, carbon and low-alloy steels, cast iron, stainless steel, Ni and Ni alloys, W, Mo, Ta, Nb and alloys, refractory metals, tool steels.
  Conditions and source

  Book page 75, chapter 3, table 3.2, Base Metal-Brazing Filler Metal Combinations. The cells that carry this class for this base metal name these partners: Cu and Cu alloys, carbon and low-alloy steels, cast iron, stainless steel, Ni and Ni alloys, W, Mo, Ta, Nb and alloys, refractory metals, tool steels. A partner is what the cell pairs the base metal with, it does not index this entry. The table lists classes, it does not qualify them, and an empty cell is never a prohibition. The class is written as the document writes it, BAl-Si becoming BAlSi here, and it is never mapped to any grade of the corpus. The table names stainless steel without a grade. The corpus carries 316L under stainless-316l, so the entry is narrower than the cell it records.

  [A]AWS Brazing Handbook, American Welding Society, chapter 3 Brazing Filler Metals and chapter 33 Electron Tubes and Vacuum Equipment

  Handbook of the American Welding Society. Three tables are read by the corpus. Table 3.2 page 75, Base Metal-Brazing Filler Metal Combinations, a two-entry matrix of base metal families whose cells carry AWS filler classes. Table 3.3 page 76, Maximum Service Temperatures Recommended for Various Brazing Filler Metal Compositions, one continuous and one short-term temperature per class. Table 33.1 page 585, Composition of Brazing Filler Metals Specially Produced for the Brazing of Vacuum Devices and Equipment, with liquidus and solidus in Fahrenheit and Celsius. The chapter, the table and the page of each statement are carried by the entry that uses it, never by this registry line.

• listedAWS class RBCuZn
  The AWS combination table lists the RBCuZn class for brazing this base metal to carbon and low-alloy steels, cast iron, tool steels.
  Conditions and source

  Book page 75, chapter 3, table 3.2, Base Metal-Brazing Filler Metal Combinations. The cells that carry this class for this base metal name these partners: carbon and low-alloy steels, cast iron, tool steels. A partner is what the cell pairs the base metal with, it does not index this entry. The table lists classes, it does not qualify them, and an empty cell is never a prohibition. The class is written as the document writes it, BAl-Si becoming BAlSi here, and it is never mapped to any grade of the corpus. The table names stainless steel without a grade. The corpus carries 316L under stainless-316l, so the entry is narrower than the cell it records.

  [A]AWS Brazing Handbook, American Welding Society, chapter 3 Brazing Filler Metals and chapter 33 Electron Tubes and Vacuum Equipment

  Handbook of the American Welding Society. Three tables are read by the corpus. Table 3.2 page 75, Base Metal-Brazing Filler Metal Combinations, a two-entry matrix of base metal families whose cells carry AWS filler classes. Table 3.3 page 76, Maximum Service Temperatures Recommended for Various Brazing Filler Metal Compositions, one continuous and one short-term temperature per class. Table 33.1 page 585, Composition of Brazing Filler Metals Specially Produced for the Brazing of Vacuum Devices and Equipment, with liquidus and solidus in Fahrenheit and Celsius. The chapter, the table and the page of each statement are carried by the entry that uses it, never by this registry line.

Against another base metal, no filler named:

• not recommendedMg and Mg Alloys
  The AWS combination table does not recommend brazing this base metal to Mg and Mg Alloys.
  Conditions and source

  Book page 75, chapter 3, table 3.2, Base Metal-Brazing Filler Metal Combinations. The cell names no filler metal of any kind, neither a grade nor an AWS class. It states something about the combination of two base metals and nothing else. The document prints this reserve under the table and it is carried here in full: X means not recommended, however special techniques may be viable for certain dissimilar metal combinations. The table names stainless steel without a grade, and the corpus carries 316L.

  [A]AWS Brazing Handbook, American Welding Society, chapter 3 Brazing Filler Metals and chapter 33 Electron Tubes and Vacuum Equipment

  Handbook of the American Welding Society. Three tables are read by the corpus. Table 3.2 page 75, Base Metal-Brazing Filler Metal Combinations, a two-entry matrix of base metal families whose cells carry AWS filler classes. Table 3.3 page 76, Maximum Service Temperatures Recommended for Various Brazing Filler Metal Compositions, one continuous and one short-term temperature per class. Table 33.1 page 585, Composition of Brazing Filler Metals Specially Produced for the Brazing of Vacuum Devices and Equipment, with liquidus and solidus in Fahrenheit and Celsius. The chapter, the table and the page of each statement are carried by the entry that uses it, never by this registry line.

Chemical affinity

What documents state about a BINARY SYSTEM, one element of a filler metal faced with one element of this material. An affinity is not a verdict on a joint: a joint brings many binaries together at once, some helpful and some harmful, and what follows is the list of those the corpus can name. The count below is not written anywhere. It falls out of the crossing of this material's elements with the composition of every filler the corpus holds, so it grows on its own the day a binary enters the corpus.

Elements of this material: Fe Cr Ni Mo, read from a composition table.

Open in the brazing abacus →