ThyssenKrupp explores steel innovations
蒂森克虜伯探索鋼材創(chuàng)新
InCar plus是蒂森克虜伯（ThyssenKrupp）公司迄今為止規(guī)模最大的內(nèi)部研發(fā)項目。該項目融合了集團內(nèi)部多學(xué)科專業(yè)知識，打造了超過40個獨立解決方案，可以在不影響車輛性能的前提下實現(xiàn)有效減重。項目也采用了多種經(jīng)驗證的高級制造技術(shù)，可以在現(xiàn)行的生產(chǎn)流程中使用。該項目的另一個特點是規(guī)?；瘧?yīng)用，公司堅持模塊輕量化設(shè)計概念，所有模塊可以在多平臺、多項目中使用。起初，項目打造了一款獨立的白車身結(jié)構(gòu)，為多種車身解決方案提供了參考基準。這款參考白車身是一輛高端中型車，具有高度代表性，其研發(fā)過程廣泛對比并參考了多家整車廠的設(shè)計。由于設(shè)計方面的優(yōu)化和高級材料的使用，該車身的輕量化指數(shù)為2.7，優(yōu)于蒂森克虜伯于2009年研發(fā)的上一款I(lǐng)nCar參考結(jié)構(gòu)。蒂森克虜伯鋼鐵北美公司技術(shù)總經(jīng)理Timo Faath與《汽車工程雜志》探討了公司的InCar plus項目，以及與此相關(guān)的有發(fā)展前景的技術(shù)。Faath負責(zé)區(qū)域汽車技術(shù)、客戶項目工程、產(chǎn)品策略和質(zhì)量管理。
InCar plus項目的創(chuàng)新成果之一是B柱的改進，采用了新型TriBond材料，您能談?wù)勓邪l(fā)過程嗎？
我們有多種B柱解決方案。我們的參考結(jié)構(gòu)采用的是MBW 1500不等溫?zé)岢尚停╰t）解決方案。我們也研發(fā)了一些熱壓成型解決方案——其中之一是MBW 1900 tt，另一個是TriBond 1400，采用了新材料研發(fā)。此外，我們還能提供一些冷壓成型解決方案，比如DP-K 700Y980T和DP-K 780Y1180。TriBond還在新材料研發(fā)階段，尚未實現(xiàn)量產(chǎn)。這種材料就像是三明治。我們會將經(jīng)過簡單處理的三層平板疊在一起，然后依次送入熱軋機、冷軋機、熱處理系統(tǒng)，最后在表面涂一層鋁。唯一需要新增的流程就是堆平板，內(nèi)板是常規(guī)的MBW 1500，而外板較薄、堅韌度也更低。這種設(shè)計的效果是…不開裂（經(jīng)下落測試和3點彎曲測試驗證），延展性更高，而堅韌度幾乎不變。在機械性能方面，材料的延伸率主要還是由內(nèi)板決定，仍然維持在4.5%-5%。新材料的彎曲角有了很大提升，常規(guī)1500的彎曲角為65°，有TriBond 1400可以提升至85°，而TriBond 1200在實驗中可彎曲至135°。所以，這才是材料真正的亮點…這是一種整體材料，可以直接通過常規(guī)的熱壓成型工藝獲得，無需修正工藝。我們對此感到很興奮。
新材料的成本如何？
在成本和減重比較方面，我們的參考結(jié)構(gòu)——MBW 1500 tt B柱的重量約為15.4kg，而TriBond 1400方案的重量可以降低至14.1kg。老實說，對我們來說計算材料成本有點困難，因為還沒有（投產(chǎn)）。與常規(guī)材料（38.80歐元）相比，我們多一個工藝步驟，所以成本確實有所增加，但今后很可能會下降（目前約為40.60歐元）。新解決方案的減重表現(xiàn)卓越，成本只是略有增加，還是很有吸引力的。我們也有一些（InCar plus項目的）解決方案，不但能夠減重，成本也有下降，因為節(jié)省了材料，而材料成本是零部件成本中最高的。有時候這些方案對于我們很有利，還是很有吸引力的。
這種材料可以實現(xiàn)其他應(yīng)用嗎？
當(dāng)然，這種材料完全可以用在B柱以外的其他領(lǐng)域。前縱梁就可以用。我曾經(jīng)展示過前縱梁的下落測試，結(jié)果看起來非常不錯。在目前的技術(shù)條件下，不能用熱壓成型工藝處理汽車前縱梁，因為部件延伸率不夠。但有了TriBond材料，我們就可以用熱壓成型工藝處理前后縱梁中需要變形的部分了?？赡苓@種應(yīng)用比B柱的應(yīng)用效果更令人滿意。其實現(xiàn)在已經(jīng)有很多高成本的B柱解決方案了，比如不等溫?zé)岢尚?，激光拼焊，連續(xù)變截面輥軋板等，但從熱壓成型工藝的角度來看，這些工藝的控制流程非常復(fù)雜。但有了TriBond，直接把材料放進熱壓成型機，就能得到一個有延展性的部件了。
您還介紹了InCar plus項目中的A柱和保險杠的應(yīng)用概念，這其中哪些技術(shù)最接近量產(chǎn)階段？
這很難回答。對InCar項目來說，我們嘗試實現(xiàn)不同水平的量產(chǎn)。其中一些解決方案客戶現(xiàn)在就能購買，還有一些仍在研發(fā)之中。這樣做是因為我們的客戶有不同的需求——一些客戶正在研發(fā)下一代汽車，而一些客戶的當(dāng)下的量產(chǎn)車型有困難，需要解決方案。我們也是在盡可能爭取更多客戶。一般來說，熱壓成型是熱門技術(shù)，我們也知道很多整車廠（特別是歐洲的公司）也在嘗試自己進行研發(fā)。我個人認為，對熱壓成型技術(shù)來說，整車廠并不希望投資于常規(guī)方法，或者說，他們一定不愿意投資于一些供應(yīng)商已經(jīng)可以提供的熱壓成型技術(shù)，他們希望獲得更精細的解決方案。（InCar項目中的）一些解決方案，比如不等溫?zé)岢尚图夹g(shù)，是非常有潛力的，我認為今后北美自貿(mào)區(qū)會越來越多地使用這些技術(shù)，而且歐洲已經(jīng)開始使用了。我們展示的所有方案，只要與熱壓成型有關(guān)，基本上都很有潛力。
InCar plus項目還會繼續(xù)嗎？還是不同的解決方案會走向獨立的研發(fā)道路？
我們一直在說，InCar plus項目研發(fā)出了40多個解決方案，但如果詳細分析整個過程，我們的研發(fā)成果遠不止于此。但并不是每一個解決方案都切實可行，或滿足我們需要的性能要求。我們選出的40個方案質(zhì)量非常高，也能帶來很多回報?，F(xiàn)在我們會一家家拜訪不同的整車廠，向他們展示我們的研發(fā)成果，希望將我們的想法融入他們的研發(fā)項目，將我們的產(chǎn)品整合至他們的汽車和業(yè)務(wù)。這樣技術(shù)也能不斷演進。一般來說，InCar中的部件不會在量產(chǎn)車中原封不動地使用，不過這也是我們研發(fā)InCar項目的原因。我們希望與客戶一直保持溝通。
作者：Ryan Gehm
來源：SAE《汽車工程雜志》
翻譯：SAE上海辦公室
ThyssenKrupp explores steel innovations
InCar plus is the most extensive internal R&D project that ThyssenKrupp has ever undertaken. It encompasses the group’s interdisciplinary expertise to generate more than 40 individual solutions for cost-effective vehicle weight reduction without sacrificing performance, as well as the use of advanced manufacturing technologies that are validated and can be implemented with current processes. Another component is scalability, with modular lightweight design concepts that can be utilized across multiple platforms and vehicle programs. The project was initiated by developing an independent body-in-white structure to serve as a reference benchmark for the various body solutions. The reference structure is a representative upper midsize class vehicle that was derived through extensive comparative studies of bodies manufactured by various OEMs. With a lightweight index of 2.7, it surpassed its previous InCar reference structure that was developed in 2009, due to improved design and advanced material utilization. Timo Faath, General Manager Technology, ThyssenKrupp Steel North America, Inc., spoke withAutomotive Engineering about the InCar plus project and some of its promising technologies. Faath is responsible for the areas vehicle technology, customer project engineering, product strategy, and quality.
One of the project’s innovations is a B-pillar featuring a new TriBond material. Can you talk about this development?
We have several different solutions for the B-pillar. Our reference structure is already a MBW 1500 tailored tempered (tt) solution. We’ve developed some hot-stamped solutions—one is MBW 1900 tt and the other is TriBond 1400, a pretty interesting new material development. And we also have some cold-stamped solutions—DP-K 700Y980T and DP-K 780Y1180. TriBond is a material development; we don’t have it in serial production yet. It’s like a sandwich material. We take three slabs, to simplify it, stacked on top of each other and run them through the hot rolling mill, the cold rolling mill, annealing, and offer it as aluminized-coated. The only process that is added is that stacking up of the slabs. The slab in the middle is a conventional MBW 1500; the thin outer slabs are lower strength. What that does for us is…no cracks [in drop tower and 3-point bending tests], higher ductility with almost the same strength level. When you look at the plain mechanical properties, the elongation is still defined by the core slab—it’s still 4.5-5% elongation. What’s really better for that material is the bending angle—for a conventional 1500 it’s about 65°, with the TriBond 1400 it goes up to 85°, and the TriBond 1200 it’s actually where the test ends at 135° bending angle. So this is the real highlight of that material…It is a monolithic material that can be stamped in a conventional hot stamping process—no process modifications necessary. So this is pretty exciting for us.
How does the new material compare cost-wise?
For a cost and weight comparison, our reference structure—the MBW 1500 tt B-pillar—weighs about 15.4 kg, and with our TriBond 1400 solution we were able to get the weight down to 14.1 kg. To be honest with you, it’s kind of difficult for us to do cost calculations on the material because it is not [in production yet]. We do see an increase compared to the conventional material [€38.80] just because we have an additional process step, but this may well go down a little [currently stated as €40.60]. So very attractive weight and slightly higher cost make the solution very attractive. We have a couple solutions [in InCar plus] where the weight reduction comes with reduced cost, just because you save material and material cost is the biggest portion of your part cost; that sometimes works in our favor. But it’s still attractive.
Any other possible applications for the material?
It doesn’t have to be a B-pillar. So we have a couple of different applications for that material. It will work for front rails as well…I showed a drop tower test of a front rail that looked very good. In today’s vehicles, you don’t use hot stamping for front rails because it’s not enough elongation in the part. But with TriBond we would actually have that option to use it in front and rear rails where deformation is required. That might actually be a better application than the B-pillars. But in B-pillars there’s a lot of expensive solutions out there—tailored tempering, tailor welded blanks, tailor rolled blanks—that are very complicated to control from a hot-stamping-process perspective. With the TriBond, you just throw it in your hot stamping press and you’ve got a ductile part.
You have also presented A-pillar and bumper concepts as part of InCar plus. Which of these technologies is closest to serial production?
That’s a tough one. Throughout the InCar project we tried to offer different serial production levels. Some of the solutions our customers can buy today. Some solutions are still under development. The reason why we do it like that is our customers—some of them work on next-generation vehicles, and some of them have a problem today with their serial production vehicle where they need a solution. So we’re trying to reach as many customers as possible. Generally speaking, hot stamping is a big topic for everybody, and we know there’s some OEMs trying to do it themselves [particularly] in Europe. Whenever OEMs invest in hot stamping, I don’t think they want to do it the conventional way—or follow what their suppliers already do for them—they want to come up with more sophisticated solutions. Some of the stuff [in InCar], tailored tempering being one of them, is very promising and I think we’ll see a lot more of that in the future in NAFTA; it’s already out there in Europe. Pretty much everything that we show [related] to hot stamping is very promising.
Is InCar plus still ongoing? Or are the individual solutions taking different development paths now?
We keep pointing out that 40 solutions were developed; actually if you look into the process, we’ve developed much more than that. But not every solution turned out to be feasible or show the performance that we needed. The 40 we selected are really good and show a lot of benefit. We do road shows—we go from OEM to OEM and present the results—we get engaged in engineering projects where we try to adopt our ideas, our products into their vehicles, into their package situation. And then typically the technologies evolve. We’re not usually seeing the exact same part as we had it in InCar in a serial production vehicle, but that’s why we do it. We want to get in conversations with our customers.
Author: Ryan Gehm
Source: SAE Automotive Engineering Magazine
蒂森克虜伯的InCar plus項目包括30個子項目，擁有超過40個獨立解決方案，致力于實現(xiàn)有成本優(yōu)勢的輕量化設(shè)計。
“一般來說，InCar中的部件不會在量產(chǎn)車中原封不動地使用，因為技術(shù)仍在不斷演進?！钡偕颂敳腡imo Faath表示。
蒂森克虜伯的InCar plus項目探索了多種B柱解決方案，包括熱壓成型和冷壓成型。
Faath表示，InCar plus的TriBond材料確實是為B柱應(yīng)用研發(fā)的，但這種技術(shù)或許更適合車輛前后縱梁的應(yīng)用。
TriBond 1200 和1400在測試中展現(xiàn)了非凡的延展性，而且不會開裂。