A Method for the Manufacturing of Liquid Metal Embrittlement Resistant Zinc Coated Steel Sheet

20:

• The method as recited in claim 19 wherein the first coating has a thickness between 600 and 750 nm or between 750 and 950 nm.

21:

• The method as recited in claim 19 wherein the recrystallization annealing is a continuous annealing.

22:

• The method as recited in claim 19 wherein the recrystallization annealing is performed in an atmosphere including from 1 to 10% of H2 at a dew point below 60° C.

23:

• The method as recited in claim 22 wherein the dew point is between −60 and −30° C.

24:

• The method as recited in claim 19 wherein the recrystallization annealing is performed in an atmosphere comprising from 1 to 10% of H2 at a dew point between −30 and +30° C.

25:

• The method as recited in claim 19 wherein in the recrystallization annealing is performed in an atmosphere comprising from 1 to 10% of H2 at a dew point between −10 and +10° C.

26:

• The method as recited in claim 19 wherein the second coating includes above 50% of zinc.

27:

• The method as recited in claim 26 wherein the second coating includes above 75% of zinc.

28:

• The method as recited in claim 27 wherein the second coating includes above 90% of zinc.

29:

• The method as recited in claim 28 wherein the second coating consists of zinc.

30:

• A coated steel sheet obtainable from the method as recited in claim 19, the coated steel sheet comprising a diffusion coating comprising nickel and iron formed through diffusion of nickel into a steel sheet, the diffusion coating being directly topped by a zinc based coating not comprising nickel.

31:

• The steel sheet as recited in claim 30 wherein the steel sheet comprises a decarburized layer having a depth of maximum 40 μm from the steel sheet surface.

32:

• A spot welded joint comprising:
• at least two metal sheets, a first of the metal sheets being the coated steel sheet as recited in claim 30, the joint containing 2 cracks or less having a size above 100 μm and wherein the longest crack has a length below 450 μm.

33:

• The spot welded joint as recited in claim 32 wherein a second of the metal sheets is a steel sheet or an aluminum sheet.

34:

• The spot welded joint as recited in claim 32 wherein a second of the metal sheets is a second coated steel sheet including a second diffusion coating including nickel and iron formed through diffusion of nickel into a second steel sheet, the second diffusion coating being directly topped by a second zinc based coating not comprising nickel.

35:

• The spot welded joint as recited in claim 32 wherein the at least two metal sheets include a third metal sheet being a steel sheet or an aluminum sheet.

36:

• A spot welded joint comprising:
• at least two metal sheets, a first of the metal sheets being the coated steel sheet obtained by the method as recited in claim 19, the joint containing 2 cracks or less having a size above 100 μm and wherein the longest crack has a length below 450 μm.

37:

• An automobile vehicle part comprising the coated steel sheet as recited in claim 30.

38:

• An automobile vehicle part comprising a coated steel sheet obtained by the method as recited in claim 19.