SE538205C2

SE538205C2 - Pressure-hardened sandwich product and process for the manufacture of the product

Info

Publication number: SE538205C2
Application number: SE1300781A
Authority: SE
Inventors: Lars Wikström; Daniel Berglund
Original assignee: Gestamp Hardtech Ab
Priority date: 2013-12-18
Filing date: 2013-12-18
Publication date: 2016-04-05
Also published as: WO2015094080A1; SE1300781A1

Abstract

538 20 Sammandrag Man tillverkar en formad tat sandwichprodukt genom presshardning av ett sandwichamne bestaende av tva platar (12,13) och mellanliggande distansmaterial (14) och lod. Man undantar amnets kanter fr6n distansmaterial och pressar ihop kanterna vid presshardningen sa all platarna dar sammanfogas tatande utan distansmaterial. Alternativt har man en tatande rand med distansmaterial hangs kanterna. 538 20 Summary A shaped tat sandwich product is made by die hardening of a sandwich blank consisting of two plates (12,13) and intermediate spacer material (14) and solder. The edges of the blank are separated from the spacer material and the edges are pressed together during the hardening of the press so that all the plates there are joined together without a spacer material. Alternatively, you have a tattered edge with spacer material hangs the edges.

Description

538 20 Presshardad sandwichprodukt samt forfarande for tillverkning av produkten Uppfinningsomrade Uppfinningen hanfor sig till en sandwichprodukt och till ett satt att tillverka en formad produkt av sandwichplat genom att man bildar ett sandwichamne av tva platar med mellanliggande distansmaterial och varmformar amnet sá att platarna och distansmaterialet sammanfogas. FIELD OF THE INVENTION The invention relates to a sandwich product and to a method of manufacturing a shaped product of sandwich plate by forming a sandwich blank of two plates with intermediate spacer material and thermoforming the blank so that the plates and the spacer material are joined.

Uppfinningens bakgrund Med presshardning av platdetaljer till fordon erhalls material med mycket hog brottgrans. Tack vare den alit hogre brottgransen kan man anvanda alit tunnare och darmed lattare plat, men detta ger den formade produkten minskad styvhet och kraven pa styvhet begransar ofta mojligheten att anvanda tunn plat. Sandwichplat är kand exennpelvis genom US 6,387,531 B1 som visar tva rostfria platar och en karna av rostfri stalull. Platarna och karnan är ihopsvetsade. De 10 2006 049 014 Al visar en varmformad produkt dar distansmaterial och tackplatar sammanfogats vid varmformningen. Background of the invention With die hardening of plate details for vehicles, materials with a very high breaking strength are obtained. Thanks to the slightly higher breaking limit, it is possible to use a thinner and thus lighter plate, but this gives the shaped product reduced stiffness and the requirements for stiffness often limit the possibility of using a thin plate. Sandwich plate is known, for example, from US 6,387,531 B1 which shows two stainless steel plates and a core of stainless steel wool. The plates and the core are welded together. De 2006 2006 049 014 A1 shows a thermoformed product in which spacer material and roofing sheets are joined during the thermoforming.

Uppfinningens syfte Det är ett andamal med uppfinningen att till fOrhallandevis lag kostnad erhalla en hoghallfast latt sandwichprodukt som har erforderlig styvhet och inte har forsamrad korrosionsbestandighet jamfOrt med en konventionell produkt av enkel plat. OBJECT OF THE INVENTION It is an object of the invention to obtain, at a relatively low cost, a hoghall-solid light sandwich product which has the required rigidity and does not have impaired corrosion resistance compared with a conventional single plate product.

Kort beskrivning av uppfinningen Uppfinningens syfte uppfylls nar man presshardar amnet och vid presshardningen tatar den formade produktens kanter. BRIEF DESCRIPTION OF THE INVENTION The object of the invention is fulfilled when the material is press-hardened and during the press-hardening the edges of the shaped product are taken.

. Uppfinningen definieras av patentkraven. . The invention is defined by the claims.

Kort beskrivning av ritningarna Figur 1 visar en hattbalk som exempel pa uppfinningen. Brief description of the drawings Figure 1 shows a hat beam as an example of the invention.

Figur 2 är en tvarsektion genom hattbalken i figur 1 tagen enligt linjen 2-2 i figur 1. Figure 2 is a cross section through the hat beam of Figure 1 taken along line 2-2 of Figure 1.

Figur 3 visar en del av amnet som produkten tillverkats av Figur 4 är en sektion tagen utmed linjen 4-4 i figur 3 Figur är en sektion motsvarande figur 2 av en modifierad produkt. 1 538 20 Figur 6 visar en del av amnet som produkten i figur 5 är tillverkad ay. Figure 3 shows a part of the blank from which the product is made. Figure 4 is a section taken along line 4-4 of Figure 3. Figure is a section corresponding to Figure 2 of a modified product. Figure 6 shows a part of the blank from which the product of Figure 5 is made ay.

Beskrivning av visat exempel pa uppfinningen Hattbalken 11 visad i figurerna 1 och 2 har en centralflans 18, sidor 19,20 och sidoflansar 21,22. Den best& av tvd stalplatar 12,13 med mellanliggande distansmaterial 14, vanligen betecknat karna. Figur 3 visar ena platen 13 med distansmaterialet 14 i form av ett bikakernonster innan det plana amnet far tillverkning av hattbalken àr fardigstallt i en fOrprocess till en sandwichpldt bestaende av de tva platarna 12,13 med mellanliggande distansmaterial 14. Distansmaterialet lamnar platarnas kanter — i detta fall hattbalkens sidoflansar 21,22 och andkanter 23 — fria och nar arnnet presshardas till att bilda hattbalken 11 pressas amnets kanter direkt ihop och lods mot varandra sasom framgar av figur 1 sa att alla produktens kanter blir tata och man erhaller en helt tat sandwichprodukt. Description of the illustrated example of the invention The hat beam 11 shown in Figures 1 and 2 has a central flange 18, sides 19,20 and side flanges 21,22. It consists of two steel plates 12,13 with intermediate spacer material 14, usually referred to as the tubes. Figure 3 shows one plate 13 with the spacer material 14 in the form of a honeycomb before the flat blank is manufactured from the hat beam is completed in a pre-process to a sandwich plate consisting of the two plates 12, 13 with intermediate spacer material 14. The spacer material leaves the edges of the plates - in this In this case, the side flanges 21,22 and duct edges 23 are free and when the hearth is hardened to form the hat beam 11, the edges of the hatch are pressed directly together and soldered to each other as shown in Figure 1 so that all product edges are taut and a completely taut sandwich product is obtained.

Tillverkningen av amnet borjar med att platarna 12,13 skars till. Ddrefter appliceras stalpulver blandat med ett bindemedel i onskat glest monster pa den plana platen 13. Sedan fors platen 13 in i en ugn vid sintringstemperatur, exv 1150 grader Celsius, sá att stalpulvret sintrar ihop och fastnar pa platen och bindemedlet fOrgasas. Eventuellt kan tillsats av lod erfordras om inte pulvret fastnar genom att sintra till platen. Pldtarna 12,13 är borstalsplat av det slag som normalt anvands vid presshardning, men de är tunnare, exv 0,2 — 0,8 mm, och stalpulvret kan vara ett borstalspulver som appliceras med en skrivare i onskad tjocklek, exv 0,5-1,5 mm. Man belagger ena platen 12,13 med lod som exempelvis kan sprayas pa eller laggas pa som en folie och lagger ihop platarna — ndr platen 13 svalnat — med det sintrade pulvret och lodet mellan platarna och fixerar platarna mot varandra till ett fardigt amne. Fixeringen kan gams med nagon enstaka svetspunkt eller pa annat satt. The production of the blank starts with the plates 12,13 being cut. Then steel powder mixed with a binder in a desired sparse sample is applied to the flat plate 13. Then the plate 13 is fed into an oven at sintering temperature, eg 1150 degrees Celsius, so that the steel powder sints together and sticks to the plate and the binder is gasified. Addition of solder may be required if the powder does not stick by sintering to the plate. Plates 12,13 are brush plate of the type normally used in press hardening, but they are thinner, eg 0.2 - 0.8 mm, and the steel powder can be a brush powder which is applied with a printer of the desired thickness, eg 0.5- 1.5 mm. One of the plates 12,13 is coated with solder which can, for example, be sprayed on or laid on as a foil and the plates are combined - when the plate 13 has cooled - with the sintered powder and the solder between the plates and the plates are fixed to each other to a finished blank. The fixation can be done with a single welding point or in another way.

Det fardigstallda amnet presshardas pa konventionellt sat!, dvs det upphettas i ugn till austenitiseringstemperatur och farflyttas sedan in till det kylda tvadelade presshardningsverktyget dar amnet snabbt formas och den formade produkten far ligga kvar nagra sekunder tills den tagit hardning med verktygsparet som fixtur. The finished blank is press-hardened in a conventional manner, ie it is heated in an oven to austenitization temperature and then transferred to the cooled two-part press-hardening tool where the blank is quickly formed and the shaped product is left for a few seconds until it has hardened with the tool pair as fixture.

Bikakemonstret gars lampligen tatare vid de delar 16 av arnnet som ska hamna i bojar pa den fardiga produkten sasom framgar av figur 3; detta far att undvika f6r stor komprimering av karnan vid formningen. 2 538 20 Under presshardningen lods stalplatarna och distansmaterialet ihop till en enhet med sandwichstruktur. Det tvadelade kylda presshardningsverktyget är ufformat sa att stalplatama i de delar av amnet som inte har distansmaterial pressas till direktkontakt och lods ihop sasom visas i figurerna 1 och 2. The honeycomb sample is suitably tightened at the parts 16 of the hearth which are to end up in buoys on the finished product as shown in Figure 3; this can be avoided for excessive compression of the core during molding. 2 538 20 During the press hardening, the steel plates and the spacer material were soldered together into a unit with a sandwich structure. The two-part cooled press hardening tool is shaped so that the steel plates in the parts of the blank which do not have spacer material are pressed into direct contact and soldered together as shown in Figures 1 and 2.

.Man kan ocksa ha andra omraden utan distansmaterial i vilka man pressar stalplatama till direktkontakt med varandra for att efterbearbetning av fardigformad produkt ska kunna gams i dessa omraden utan att sandwichkonstruktionens tathet aventyras. It is also possible to have other areas without spacer material in which the steel plates are pressed into direct contact with each other so that post-processing of finished product can be played in these areas without compromising the tightness of the sandwich construction.

Sidoflansarna 19,20 men aven hattbalkens andkanter 23 ska ha platarna sammanlodda utan distansmaterial sa att hela sandwichkonstruktionen blir tat och darmed far god korrosionsbestandighet. Andra sandwichprodukter an en balk kan pa samma salt g6ras tata. Det maste dock finnas hal genom vilka luft kan stromma in i sandwichprodukten under kylningen. Onskas helt tat produkt kan sadana hal svetsas igen pa fardig produkt. Det kan naturligtvis finnas produkter som inte behover vara tata och darfor har flagon del av sin kant Open. The side flanges 19,20 but also the duct edges 23 of the hat beam must have the plates soldered together without spacer material so that the entire sandwich construction is tat and thus has good corrosion resistance. Other sandwich products on a beam can be made with the same salt. However, there must be slippery through which air can flow into the sandwich product during cooling. If a completely sealed product is desired, such a hall can be welded back on the finished product. Of course, there may be products that do not need to be tata and therefore the flake has part of its edge Open.

Figur 5 visar ett modifierat utforande dar produkten gjorts tat genom att den har en tat rand 25 av distansmaterial, som bildar produktens kanter i stallet fOr att platarna 12,13 är i kontakt. Randen kan vara av sintrat pulver med lod som resten av distansmaterialet, men kan vara en solid rand av stal. Figur 6 visar platen 13 i ufforandet enligt fig 5 med tata randen 25. Figure 5 shows a modified embodiment where the product has been made in that it has a taken edge 25 of spacer material, which forms the edges of the product in the stable so that the plates 12,13 are in contact. The stripe can be of sintered powder with solder like the rest of the spacer material, but can be a solid stripe of steel. Figure 6 shows the plate 13 in the embodiment according to Figure 5 with the tata edge 25.

Sintrat pulver har visats som exempel pa distansmaterial. Man kan alternativt ha andra distansmaterial. Ena platen kan exempelvis ha intryckta bulor som fungerar som distansmaterial. Bulorna ger dock en viss forsamring av den platens hallfasthet 3 Sintered powder has been shown as an example of spacer material. You can alternatively have other spacer materials. One plate may, for example, have depressed bumps that act as a spacer material. However, the bumps give a certain accumulation of the plate strength 3

Claims

5 HP1307 Claims

1. Method of manufacturing a shaped product of sandwich sheet by making asandwich blank of two sheets (12, 13) with spacer material (14) and solderin between, and hot forming the blank so that the sheets and spacer mate-rial are joined, characterised by that the blank is press-hardened to the product and, at the press hardening, the product's edges are sealed.

2. Method according to claim 1, characterised by that a loose pattern (14) ofmetal powder and binding agent is placed on one sheet and the exposedpowder is sintered together in a pre-process to make the spacer material and is bound to said one sheet.

3. Method according to claim 1, characterised by that a sheet is punched to a loose pattern and used as spacer material.

4. Method according to claim 1, characterised by that edges (21, 22) of theblank are excepted from the spacer material (14), and then during thepress hardening the sheets (12, 13) are pressed to one another at saidedges so that the sheets are joined there without spacer material.

5. Method according to claim 4, characterised by that the edges are re-worked.

6. Method according to claims 1, 2 or 3, characterised by that spacer mate- rial (14) is placed out to the outer edges of the sheets so that the productis tight along the outer edges of the sheets.

7. Sandwich product comprising two formed steel sheets (12, 13) with spacermaterial (14) lying in between, characterised by that the product is press-hardened and its edges (21, 22, 23; 25) are tight.

8. Sandwich product according to claim 7, characterised by that the spacer material (14) comprises a sintered steel powder laid out in a pattern. 10. 11. 12. 6 HP1307 Sandwich product according to claim 7, characterised by that the spacer material (14) comprises a metal sheet punched to a loose pattern. Sandwich product according to claim 7 or 8, characterised by that theedges (21, 22, 23) of the product lack spacer material and have sheets di- rectly joined to one another. Sandwich product according to any of claims 7-10, characterised by that the edges of the product have a rim of sealing spacer material (25). Sandwich product according to any of claims 7-11, characterised by that the pattern of the spacer material (14) is tighter at the bends in the productthan on its flat surfaces.