Press hardened steel (PHS) welding blank with enhanced toughness

Abstract

The invention relates to a press hardened steel (PHS) welding blank with enhanced toughness. A method of manufacturing a component includes providing a first PHS blank including an aluminum silicon (AlSi) coating; providing a second PHS blank, wherein the second PHS blank comprises chromium (Cr) at a higher concentration than the first PHS blank and does not comprise an aluminum silicon (AlSi) coating; welding the first PHS blank to the second PHS blank to form a welded blank comprising a weld seam between the first PHS blank and the second PHS blank; transferring the welding blank into a furnace; soaking the welding blank in a furnace at a preset temperature for a preset time; and pressing, shaping and quenching the welding blank in a press / press to form the component.

Description

Technical Field

[0001] The present disclosure relates to the manufacture of components using press hardened steel (PHS), and more particularly to welded, austenitized, and formed, pressed and quenched PHS billets. Background Art

[0002] The information provided in this section is for the purpose of generally presenting the background of the present disclosure. The work of the presently named inventors, to the extent described in this section, and aspects of the specification that may not constitute prior art at the time of filing are neither expressly nor impliedly admitted to be prior art to the present disclosure.

[0003] The present disclosure relates to the manufacture of components using press hardened steel (PHS), and more particularly to welded, austenitized, and formed, pressed and quenched PHS billets.

[0004] Press hardening steel (PHS) increases the height of steel. PHS is often used for load-bearing parts of vehicles, construction equipment and / or other devices. In the press hardening process, two or more PHS blanks are welded together and then soaked for a predetermined time in the temperature range used for austenitizing. After austenitizing, the welded PHS blanks are transferred to a punch / press and formed, pressed and quenched using one or more dies.

[0005] When the PHS blank is uncoated, an oxide layer may form on the blank surface during austenitization and transfer to the punch / press. As a result, the oxide layer needs to be removed after forming, pressing and quenching. For example, the oxide layer can be descaled by shot peening, which increases costs and production cycle time.

[0006] To avoid the formation of an oxide layer, the PHS billet may be coated with a coating that inhibits the formation of an oxide layer. For example, the PHS billet may be coated with an aluminum silicon alloy (AlSi) to inhibit the oxide coating and avoid the cost and time required to remove the oxide layer. Summary of the invention

[0007] A method for manufacturing a component includes providing a first PHS billet including an aluminum silicon (AlSi) coating; providing a second PHS billet, wherein the second PHS billet includes chromium (Cr) at a higher concentration than the first PHS billet and does not include an aluminum silicon (AlSi) coating; welding the first PHS billet to the second PHS billet to form a welded billet including a weld between the first PHS billet and the second PHS billet; transferring the welded billet to a furnace; heat soaking the welded billet in the furnace at a predetermined temperature for a predetermined time; and pressing, forming and quenching the welded billet in a stamping machine / press to form a component.

[0008] In other features, the predetermined temperature is 900° C. to 950° C. The second PHS billet comprises iron (Fe); 0.05 wt % to 0.35 wt % carbon (C); 0.05 wt % to 3.0 wt % manganese (Mn); 1.2 wt % to 12 wt % chromium (Cr); and 0.3 wt % to 2.0 wt % silicon (Si).

[0009] In other features, the second PHS billet includes 0.01 wt % to 1.5 wt % nickel (Ni); 0.01 wt % to 0.5 wt % vanadium (V); 0.01 wt % to 0.3 wt % niobium (Nb); and 0.01 wt % to 0.3 wt % titanium (Ti). The second PHS billet includes 0.01 wt % to 1.5 wt % Ni. The second PHS billet includes 0.01 wt % to 0.5 wt % vanadium (V). The second PHS billet includes 0.01 wt % to 0.3 wt % niobium (Nb). The second PHS billet includes 0.01 wt % to 0.3 wt % titanium (Ti). Chromium (Cr) is 1.2 wt % to 6 wt % and the ratio of Cr / Si is greater than 0.5 and less than 3.

[0010] In other features, after pressing, forming and quenching, the second PHS billet includes a surface oxide layer having a thickness of less than 1.5 μm. After pressing, forming and quenching, the second PHS billet includes 0.1 volume % to 10 volume % Cr-rich carbides. After pressing, forming and quenching, the weld includes less than 0.8 weight % Al and greater than 0.5 weight % Cr. After pressing, forming and quenching, the microstructure of the weld includes less than 5 volume % ferrite, greater than 80 volume % martensite.

[0011] A component including two or more welded PHS billets includes a first PHS billet including an aluminum silicon (AlSi) coating and a second PHS billet. The second PHS billet includes chromium at a higher concentration than the first PHS billet and does not include the aluminum silicon (AlSi) coating and a weld between the first PHS billet and the second PHS billet.

[0012] In other features, the second PHS billet comprises iron (Fe); 0.05 wt % to 0.35 wt % carbon (C); 0.05 wt % to 3.0 wt % manganese (Mn); 1.2 wt % to 12 wt % chromium (Cr); and 0.3 wt % to 2.0 wt % silicon (Si).

[0013] In other features, the second PHS billet further comprises at least one of 0.01 wt % to 1.5 wt % nickel (Ni); 0.01 wt % to 0.5 wt % vanadium (V); 0.01 wt % to 0.3 wt % niobium (Nb); and 0.01 wt % to 0.3 wt % titanium (Ti).

[0014] In other features, the chromium (Cr) is 1.2 wt % to 6 wt %, and the ratio of Cr / Si is greater than 0.5 and less than 3. After hot stamping, the second PHS blank contains 0.1 vol % to 10 vol % Cr-rich carbides.

[0015] In other features, after pressing, forming and quenching, the weld comprises less than 0.8 wt% Al and greater than 0.5 wt% Cr, and the microstructure of the weld comprises less than 5 volume % ferrite, greater than 80 volume % martensite.

[0016] In other features, the component includes one of a B-pillar and a door ring.

[0017] The present disclosure includes the following aspects:

[0018] 1. A method for manufacturing a component, comprising:

[0019] providing a first PHS blank including an aluminum silicon (AlSi) coating;

[0020] providing a second PHS blank,

[0021] wherein the second PHS blank contains chromium (Cr) at a higher concentration than the first PHS blank and does not include an aluminum silicon (AlSi) coating;

[0022] welding the first PHS blank to the second PHS blank to form a welded blank including a weld between the first PHS blank and the second PHS blank;

[0023] transferring the welded blank to a furnace;

[0024] soaking the weld blank in a furnace at a predetermined temperature for a predetermined period of time; and

[0025] The welded blanks are pressed, formed and quenched in a stamping machine / press to form the components.

[0026] 2. The method of aspect 1, wherein the predetermined temperature is 900°C to 950°C.

[0027] 3. The method of aspect 1, wherein the second PHS blank comprises:

[0028] Iron (Fe);

[0029] 0.05 wt% to 0.35 wt% of carbon (C);

[0030] 0.05 wt % to 3.0 wt % manganese (Mn);

[0031] 1.2 to 12 wt % chromium (Cr); and

[0032] 0.3 wt % to 2.0 wt % of silicon (Si).

[0033] 4. The method of aspect 3, wherein the second PHS blank comprises:

[0034] 0.01 wt % to 1.5 wt % nickel (Ni);

[0035] 0.01 wt % to 0.5 wt % of vanadium (V);

[0036] 0.01 wt% to 0.3 wt% niobium (Nb); and

[0037] 0.01 wt% to 0.3 wt% of titanium (Ti).

[0038] 5. The method of aspect 3, wherein the second PHS billet comprises 0.01 wt. % to 1.5 wt. % Ni.

[0039] 6. The method of aspect 3, wherein the second PHS billet contains 0.01 wt. % to 0.5 wt. % vanadium (V).

[0040] 7. The method of aspect 3, wherein the second PHS billet comprises 0.01 wt. % to 0.3 wt. % niobium (Nb).

[0041] 8. The method of aspect 3, wherein the second PHS billet comprises 0.01 wt % to 0.3 wt % titanium (Ti).

[0042] 9. The method of aspect 3, wherein the chromium (Cr) is 1.2 wt% to 6 wt% and the ratio of Cr / Si is greater than 0.5 and less than 3.

[0043] 10. The method of aspect 3, wherein after pressing, forming and quenching, the second PHS blank comprises a surface oxide layer having a thickness of less than 1.5 μm.

[0044] 11. The method of aspect 1, wherein after pressing, forming and quenching, the second PHS billet contains 0.1 volume % to 10 volume % of Cr-rich carbides.

[0045] 12. The method of aspect 1, wherein after pressing, forming and quenching, the weld contains less than 0.8 wt. % Al and greater than 0.5 wt. % Cr.

[0046] 13. The method of aspect 1, wherein after pressing, forming and quenching, the microstructure of the weld comprises less than 5 volume % ferrite and greater than 80 volume % martensite.

[0047] 14. A component comprising two or more welded PHS blanks, comprising:

[0048] a first PHS blank including an aluminum silicon (AlSi) coating;

[0049] The second PHS blank,

[0050] wherein the second PHS blank contains chromium at a higher concentration than the first PHS blank and does not include the aluminum silicon (AlSi) coating; and

[0051] A weld between the first PHS blank and the second PHS blank.

[0052] 15. The component of aspect 14, wherein the second PHS blank comprises:

[0053] Iron (Fe);

[0054] 0.05 wt% to 0.35 wt% of carbon (C);

[0055] 0.05 wt % to 3.0 wt % manganese (Mn);

[0056] 1.2 to 12 wt % chromium (Cr); and

[0057] 0.3 wt % to 2.0 wt % of silicon (Si).

[0058] 16. The component of aspect 15, wherein the second PHS blank further comprises at least one of the following:

[0059] 0.01 wt % to 1.5 wt % nickel (Ni);

[0060] 0.01 wt % to 0.5 wt % of vanadium (V);

[0061] 0.01 wt% to 0.3 wt% niobium (Nb);

[0062] and 0.01 wt % to 0.3 wt % of titanium (Ti).

[0063] 17. The component of aspect 15, wherein the chromium (Cr) is 1.2 wt % to 6 wt %, and the ratio of Cr / Si is greater than 0.5 and less than 3.

[0064] 18. The component of aspect 15, wherein after hot stamping, the second PHS blank comprises 0.1 vol% to 10 vol% Cr-rich carbides.

[0065] 19. The component of aspect 14, wherein:

[0066] After pressing, forming and quenching:

[0067] The weld contains less than 0.8 wt. % Al and more than 0.5 wt. % Cr, and

[0068] The microstructure of the weld includes less than 5 volume % ferrite and more than 80 volume % martensite.

[0069] 20. The component of aspect 14, wherein the component comprises one of a B-pillar and a door ring.

[0070] Further areas of applicability of the present disclosure will become apparent from the detailed description, claims and drawings.The detailed description and specific examples are intended for illustrative purposes only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] The present disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0072] Figure 1 is a functional block diagram of an example of a method for welding two or more PHS weld blanks, soaking the weld blanks in a furnace, and forming, pressing, and quenching the weld blanks to form a component according to the present disclosure;

[0073] Figure 2A An example of a cross section of an AlSi coated PHS billet during welding is shown;

[0074] Figure 2B An example of a cross section of an AlSi coated PHS billet after welding is shown;

[0075] Figure 2C An example of a cross section of an AlSi-coated PHS billet after welding and forming is shown;

[0076] Figure 3A and 3B Examples of enlarged cross-sections of welds between AlSi-coated PHS blanks during welding and stamping are shown, respectively;

[0077] Figure 3C shows an example of fracture in a weld between AlSi-coated PHS blanks after stamping;

[0078] Figure 4is a flow chart of an example of a method for welding a first AlSi-coated PHS billet and a chromium-added PHS billet, soaking the weld billet in a furnace, and forming, pressing, and quenching the weld billet after heating according to the present disclosure;

[0079] Figure 5 An example of aluminum (Al) and chromium (Cr) content in a weld between an AlSi-coated PHS billet and a Cr-added PHS billet according to the present disclosure is shown;

[0080] Figure 6 is a graph showing engineering stress as a function of engineering strain percentage for base metal and various welded PHS billets including base metal;

[0081] Figure 7 An example of the hardness across a weld between an AlSi coated PHS billet and a Cr added PHS billet according to the present disclosure is shown;

[0082] Fig. 8A is a side view showing one example of an AlSi coated PHS billet welded to a Cr-added PHS billet having different thicknesses arranged between liquid cooling dies according to the present disclosure;

[0083] Figure 8B is a graph showing examples of temperature versus time to show cooling rates required for different microstructures; and

[0084] Fig. 9 is a plan view showing an example of a door ring including more than two PHS welded blanks.

[0085] Among the drawings, reference numerals may be repeated to identify similar and / or identical elements. DETAILED DESCRIPTION

[0086] Although the component manufacturing method using laser welding of press hardened steel (PHS) billets according to the present disclosure is described in the context of vehicle structural components, the method may be used in other manufacturing applications.

[0087] In the press hardening process of steel, two or more PHS billets are laser welded, heated to austenitizing temperature for a predetermined time, transferred to a punch / press while hot, and formed, pressed and quenched between two or more dies. To avoid the formation of an oxide layer, the PHS billets are coated with an aluminum silicon alloy (AlSi) to inhibit oxide formation and avoid the cost and time required to remove the oxide after quenching, pressing and forming.

[0088] The AlSi coating dissolves into the weld between PHS billets during welding (e.g., laser welding), which results in the formation of brittle intermetallic compounds and / or soft ferrite. Current solutions to this problem (e.g., filler wire and laser ablation) are expensive and complex to implement at high production levels.

[0089] In the process of manufacturing a component using laser welded PHS billets according to the present disclosure, a first PHS billet including an AlSi coating is welded to a second PHS billet not including the AlSi coating. The second PHS billet contains a higher level of chromium (Cr) than the first PHS billet. After welding, the welded PHS billet is transferred to a furnace for austenitization. After austenitization, the welded PHS billet is transferred to a stamping press / press for quenching, pressing and forming of the component.

[0090] The use of the second PHS billet reduces coating contamination in the weld. The addition of Cr to the second PHS billet increases the hardenability of the weld, which improves the strength and toughness of the component. The method according to the present disclosure allows a greater number of thickness / material combinations to be used to join laser welded PHS billets.

[0091] Now refer to Figure 1 , the first PHS blank 110 includes an AlSi coating. The second PHS blank 112 does not include the AlSi coating and includes an increased amount of chromium (Cr) relative to the first PHS blank, as will be further described below. The first PHS blank 110 is welded (e.g., by a laser 116 and a scanner 114) to the second PHS blank 112 to form a welded blank 113.

[0092] After welding, the welded blank 113 is transferred to the furnace 114 to soak the welded blank 113 at a temperature within a predetermined temperature range for austenitization. In some examples, the predetermined temperature range is 900° C. to 950° C. After austenitization in the furnace 120, the welded blank 113 is transferred to a punch / press 140 including two or more dies 144 for forming, pressing and quenching to produce a component 150. In some examples, a conveyor 120, a robot with an end effector 134, or other device can be used to transfer the welded blank 113 to the furnace 120, through the furnace 120, and / or between the furnace 120 and the punch / press 140.

[0093] Now refer to Figures 2A to 2CDuring welding, Al from the AlSi coating (shown in white) dissolves into the weld between the PHS blanks (as described in “A review on the laser welding of coated 22MnB5 press-hardened steel and its impact on the production of tailor-welded blanks”, Khan, Razmpoosh, and Zhou, March 26, 2020, pp. 447-467 (https: / / doi.org / 10.1080 / 13621718.2020.1742472)). Figures 2A to 2C In the figure, both PHS blanks are coated with AlSi coating. Figure 2A The PHS billet during welding is shown in Figure 2B The PHS billet after welding is shown in FIG. Figure 2C , a PHS blank is shown after forming, pressing and quenching. The AlSi coating leads to the formation of brittle intermetallic compounds and / or soft ferrite.

[0094] exist Figures 3A to 3C , a weld between two PHS blanks, both coated with AlSi, is shown (as described in “A review on the laser welding of coated 22MnB5 press-hardened steel and its impact on the production of tailor-welded blanks”, Khan, Razmpoosh and Zhou, March 26, 2020, pp. 447-467 (https: / / doi.org / 10.1080 / 13621718.2020.1742472)). Figure 3A In the figure, the weld between two PHS billets after welding is shown. It can be seen that Al introduces delta-ferrite formation during the welding process. Figure 3B In the figure, a weld is shown between two PHS billets after forming, pressing and quenching. Al introduces α-ferrite formation during forming, pressing and quenching. Figure 3C In the process, fracture occurs at the weld after forming, pressing and quenching.

[0095] Now refer to Figure 4, a method 200 for manufacturing a component is shown. At 220, an AlSi coated PHS billet is welded to a Cr added PHS billet. In some examples, laser welding is used. At 230, the welded billet is transferred to a furnace. At 232, the welded billet is soaked in the furnace at a predetermined temperature for a predetermined time. In some examples, the predetermined temperature is 900°C to 950°C. In some examples, the predetermined time is sufficient to austenitize the welded billet. At 240, the welded billet is transferred to a stamping press / press for quenching, forming, and pressing to form the component.

[0096] Now refer to Figure 5 , shows a welded blank before hot stamping. In the Cr-added PHS blank (marked at 310), the Al content is about 0 wt% and the Cr content is greater than 1.5 wt%. At the weld (marked at 320), the Al content is less than about 0.8 wt% and the Cr content is greater than 0.5%. At the PHS blank with AlSi coating (marked at 330), the Al content is about 0 wt% and the Cr content is about 0 wt%.

[0097] Now refer to Figure 6 , engineering stress in MPa is shown as a function of engineering strain percentage for various samples including base metal and welded PHS billets. Performance of a first sample 350 including an AlSi coated PHS billet welded to an AlSi coated PHS billet (e.g., AlSi coated 22MnB5 steel) without a filler wire or ablation. The first sample suffered premature fracture at the weld. Performance of a second sample 260 including an uncoated PHS billet welded to an AlSi coated PHS billet. The second sample 260 had higher tensile properties than the first sample 350 and suffered ductile fracture at the base metal. Performance of a third sample 360 ​​including a base metal of AlSi coated 22MnB5. Performance of a fourth sample 370 including a base metal of uncoated steel.

[0098] Now refer to Figure 7 , shows the hardness from the first PHS billet with AlSi coating to the weld and then to the second PHS billet (AlSi coating without Cr addition). The hardness value transitions smoothly on the welded PHS billets without a sudden drop in hardness.

[0099] Now refer to Fig. 8A and 8B , welded PHS blanks according to the present disclosure may be manufactured with additional thickness combinations. Fig. 8AIn the embodiment, first and second welding blanks 410 and 420 having different thicknesses (e.g., 1.8 mm and 1.2 mm) are arranged between dies 430 and 440 having water cooling channels. Due to the lower thickness, an air gap is formed between the second welding blank 420 and the die 430. The Cr-added PHS blank has improved hardenability. Due to the change in the microstructure of the Cr-added PHS blank, such as Figure 8B It can be seen that a lower cooling rate can be used. The critical cooling rate can be as low as 5°C / sec. In other words, the Cr-added PHS billet can be hardened by air cooling.

[0100] Now refer to Fig. 9 Examples of parts incorporating welded PHS billets (including PHS billets with AlSi coating and PHS billets with added Cr) include B-pillars, door rings, and / or other parts. The part may include more than two PHS billets. For example, the B-pillar may include a PHS billet with an AlSi coating welded to a PHS billet with added Cr. For example, a door assembly may include an additional PHS billet joined.

[0101] Fig. 9 The door ring 500 in the example of FIG. 5 includes frame portions 510, 514, 518, 522, 524, and 528 that are joined to form the door ring 500. A mixture of PHS blanks with an AlSi coating, a PHS blank with Cr added, and / or an uncoated PHS blank can be used. In this example, frame portion 510 may include 1.2 mm 1200 MPa of PHS with Cr added. Frame portion 514 may include 1.2 mm 2000 MPa of bare PHS (conventional). Frame portion 518 may include 1.4 mm 1700 MPa of PHS with Cr added. Frame portion 522 may include 1.8 mm 600 MPa of PHS with AlSi coating. Frame portion 524 may include 1.2 mm 1700 MPa of PHS with Cr added. Frame portion 528 may include 1.3 mm 1500 MPa of PHS with AlSi coating. It is understood that other types of components may be manufactured.

[0102] In some examples, the Cr-added PHS billet includes iron (Fe), 0.05 wt % to 0.35 wt % carbon (C), 0.05 wt % to 3.0 wt % manganese (Mn), 1.2 wt % to 12 wt % chromium (Cr), 0.3 wt % to 2.0 wt % silicon (Si), 0 wt % to 1.5 wt % nickel (Ni), 0 wt % to 0.5 wt % vanadium (V), 0 wt % to 0.3 wt % niobium (Nb), and 0 wt % to 0.3 wt % titanium (Ti).

[0103] In some examples, the Cr-added PHS billet includes one or more of 0.01 wt % to 1.5 wt % Ni, 0.01 wt % to 0.5 wt % vanadium (V), 0.01 wt % to 0.3 wt % niobium (Nb), and / or 0.01 wt % to 0.3 wt % titanium (Ti).

[0104] In some examples, for oxidation resistance during hot stamping, when Cr<6 wt%, the ratio of Cr / Si is greater than 0.5 and less than 3. In some examples, the Ni concentration is increased to further improve the toughness of the fusion zone.

[0105] In some examples, the microstructure of the bare PHS blank with Cr added after hot stamping includes a surface oxide layer having a thickness of less than 1.5 μm. The surface oxide layer contains Fe-Cr-Si-Mn oxides. In some examples, the steel contains 0.1 volume % to 10 volume % Cr-rich carbides. In some examples, the Cr in the carbides is 10 wt % to 51 wt % and the size of the carbides is 25 nm to 400 nm.

[0106] In some examples, the chemical composition of the weld after welding includes <0.8 wt% Al, >0.5 wt% Cr (e.g., averaged at different regions to include segregation). In other examples, the chemical composition of the weld after welding includes Al<(0.8 wt% + 1 / 2Al in base steel 1 + 1 / 2Al in base steel 2).

[0107] The microstructure of the weld after laser welding and hot stamping comprises <5 volume % ferrite, >80 volume % martensite, the remaining volume % comprising bainite and / or retained austenite, and <1 volume % Cr-rich carbides.

[0108] The mechanical properties of the weld after laser welding and hot stamping include tensile fracture occurring away from the weld. The impact toughness is not less than 80% of the softer base steel. The hardness is not less than 90% of the softer base steel.

[0109] The foregoing description is merely illustrative, and is by no means intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in various forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because after studying the drawings, the specification and the appended claims, other modifications will become apparent. It should be understood that, without changing the principle of the present disclosure, one or more steps in the method can be performed in different orders (or simultaneously). In addition, although each embodiment is described above as having certain features, any one or more of those features described in any embodiment of the present invention can be implemented in any of other embodiments and / or combined with the features of any of other embodiments, even if the combination is not explicitly described. In other words, the embodiments described are not mutually exclusive, and the replacement of one or more embodiments with each other remains within the scope of the present disclosure.

[0110] Various terms are used to describe the spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.), including "connected," "engaged," "coupled," "adjacent," "immediately adjacent," "on top," "above," "below," and "disposed." Unless explicitly described as "directly," when the relationship between a first and a second element is described in the above disclosure, the relationship can be a direct relationship in which there are no other intervening elements between the first and second elements, but can also be an indirect relationship in which there are one or more intervening elements (spatially or functionally) between the first and second elements. As used herein, the phrase at least one of A, B, and C should be interpreted to mean a logical (A or B or C) using a non-exclusive logical "or," and should not be interpreted to mean "at least one of A, at least one of B, and at least one of C."

[0111] In the drawings, the direction of the arrow, as indicated by the arrow, generally indicates the flow of information (such as data or instructions) related to the diagram. For example, when component A and component B exchange various information, but the information transmitted from component A to component B is related to the diagram, the arrow may point from component A to component B. The unidirectional arrow does not imply that no other information is transmitted from component B to component A. In addition, for information sent from component A to component B, component B may send a request for the information or a confirmation of receipt of the information to component A.

Claims

1. A method for manufacturing a component, comprising: providing a first PHS blank including an aluminum silicon (AlSi) coating; providing a second PHS blank, wherein the second PHS blank contains chromium (Cr) at a higher concentration than the first PHS blank and does not include an aluminum silicon (AlSi) coating; welding the first PHS blank to the second PHS blank to form a welded blank including a weld between the first PHS blank and the second PHS blank; transferring the welded blank to a furnace; soaking the welding blank in a furnace at a predetermined temperature for a predetermined period of time; and The welded blanks are pressed, formed and quenched in a stamping machine / press to form the components.

2. The method of claim 1, wherein the predetermined temperature is 900°C to 950°C.

3. The method of claim 1, wherein the second PHS blank comprises: Iron (Fe); 0.05 wt% to 0.35 wt% of carbon (C); 0.05 wt % to 3.0 wt % manganese (Mn); 1.2 to 12 wt % chromium (Cr); and 0.3 wt % to 2.0 wt % of silicon (Si).

4. The method of claim 3, wherein the second PHS blank comprises: 0.01 wt % to 1.5 wt % nickel (Ni); 0.01 wt % to 0.5 wt % of vanadium (V); 0.01 wt% to 0.3 wt% niobium (Nb); and 0.01 wt% to 0.3 wt% of titanium (Ti).

5. The method of claim 3, wherein the second PHS billet comprises 0.01 wt% to 1.5 wt% Ni.

6. The method of claim 3, wherein the second PHS billet comprises 0.01 wt% to 0.5 wt% vanadium (V).

7. The method of claim 3, wherein the second PHS billet comprises 0.01 wt% to 0.3 wt% niobium (Nb).

8. The method of claim 3, wherein the second PHS billet comprises 0.01 wt% to 0.3 wt% titanium (Ti).

9. The method of claim 3, wherein the chromium (Cr) is 1.2 wt% to 6 wt% and the ratio of Cr / Si is greater than 0.5 and less than 3.

10. The method of claim 3, wherein after pressing, forming and quenching, the second PHS blank comprises a surface oxide layer having a thickness of less than 1.5 μm.

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