1、Aluminum Auto-Body JoiningOther SAE books of interest: The Multi Material Lightweight Vehicle (MMLV) Project By Tim Skszek, Jeff Conklin, Matt Zaluzec, and David Wagner (Product Code: PT-170) Fundamentals of Automobile Body Structure Design By Donald E. Malen (Product Code: R-394) For more informati
2、on or to order a book, contact: SAE INTERNATIONAL 400 Commonwealth Drive Warrendale, PA 15096 Phone: +1.877.606.7323 (U.S. and Canada only) or +1.724.776.4970 (outside U.S. and Canada) Fax: +1.724.776.0790 Email: CustomerServicesae.org Website: books.sae.orgAluminum Auto-Body Joining Edited By Georg
3、e N. Bullen Warrendale, Pennsylvania, USACopyright 2016 SAE International. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, distributed, or transmitted, in any form or by any means without the prior written permission of SAE International. For permiss
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7、 appropriate professional should be sought. ISBN-Print 978-0-7680-8252-4 ISBN-PDF 978-0-7680-8265-4 ISBN-epub 978-0-7680-8267-8 ISBN-prc 978-0-7680-8266-1 To purchase bulk quantities, please contact SAE Customer Service e-mail: CustomerServicesae.org phone: +1.877.606.7323 (inside USA and Canada) +1
8、.724.776.4970 (outside USA) fax: +1.724.776.0790 Visit the SAE Bookstore at books.sae.org 400 Commonwealth Drive Warrendale, PA 15096 E-mail: CustomerServicesae.org Phone: +1.877.606.7323 (inside USA and Canada)+1.724.776.4970 (outside USA) Fax: +1.724.776.0790v Table of Contents Introduction . 1 In
9、tegration and Lightweight Design in Automotive Doors (2015-26-0242) 5 Rolf Bcker, Brose Fahrzeugteile GmbH Jugraj Singh, Chrysler Group LLC; Ravi Verma, General Motors Company Simulation of Galvanic Corrosion of Aluminum Materials for Vehicles (2010-01-0724) 23 Takahiro Mizukami, Honda Structure to
10、Assist in Prevention of Bimetallic Corrosion of Hybrid Doors (2013-01-0386) 35 Shoji Kimura, Honda R Kevin Gong, Constellium; Guowu Shen, Jie Liang, and James Chen, CanmetMATERIALS Application of an FSW Continuous Welding Technology for Steel and Aluminum to an Automotive Subframe (2013-01-0372) 47
11、Shosuke Ohhama and Tsunehisa Hata, Honda R Takanori Yahaba, Honda Motor Co., Ltd. Suzuka Factory; Tsutomu Kobayashi, Tetsuya Miyahara, and Mitsuru Sayama, Honda R Duane Detwiler and Daniel Paolini, Honda R Boris Baeumler, DEPRAG Inc.; Laurence Claus, EJOT GmbHvi New Adhesive Bonding Surface Treatmen
12、t Technologies for Lightweight Aluminum-Polypropylene Hybrid Joints in Semi-Structural Applications (2011-01-0217). 65 Danick Gallant and Vronique Savard, Aluminium Technology Centre Sandwich Panels with Corrugated Core - A Lightweighting Concept with Improved Stiffness (2014-01-0808) 79 Pankaj K. M
13、allick and Rajesh Boorle, University of Michigan About the Editor 871 Introduction Heavy-duty pickup trucks have sustained United States and global sales numbers over the past decade, and even have experienced increased sales in 2015. However, their future market viability will be affected by the im
14、plementation of new United States Federal CAFE 2 environmental standards. Gas and diesel engine, as well as powertrain technology, have matured, and the remaining innovative solutions for increasing fuel efficiency are limited. Achieving lighter weight is one of the last options available to meet CA
15、FE 2 standards while retaining the popular size, horsepower, and utility offered by heavy-duty pickup truck vehicles. Lighter weight translates to higher fuel efficiency. It should be noted that the decade-long sustained sales occurred through a period when gas prices peaked at historic levels in th
16、e United States. While sales did decline when average gas prices spiked at $4.49 a gallon 1in July 2008, sales rapidly recovered in subsequent years. Additionally, new heavy-duty truck sales were offset by increased owner retention of their older heavy-duty trucks. The number of heavy-duty pickup tr
17、ucks in the United States stayed constant. Some of the loyalty for these types of vehicles can be attributed to engine and powertrain technology innovations that have improved fuel efficiency while retaining the owners desired horsepower and torque. However, consistent new vehicle sales and retentio
18、n of these highly utilitarian vehicles through gas price volatility reflect a degree of owner insensitivity to fuel cost increases. While owners may be insensitive to fuel cost, federal fuel efficiency requirements are driving producers of heavy-duty pickup trucks to find ways to meet future fuel ef
19、ficiency standards. Meeting the seemingly contradictory requirements of higher federal fuel efficiency standards while supplying the customers desire for size, utility, horsepower, and torque has led producers to leave the comfort of steel and look to other lightweight materials. The move to lighter
20、-weight materials is not limited to heavy- duty pickup trucks, nor is it new to road vehicles. Hybrid and electric vehicle producers recognize the relationship between energy storage, energy consumption, and weight. In the early versions of these vehicles, size was reduced to minimize weight. In gas
21、-driven vehicles, size was also reduced, resulting in small cars that have not translated as expected to popularity and sales. A minimum size meets human comfort and utility requirements, and that, in turn, drives demand. It is a fact of physics: larger vehicles are safer than smaller vehicles. Cons
22、umers shopping for a fuel-efficient vehicle are already gravitating toward smaller cars. By doing so, they put themselves at greater risk of injury or death in an accident. Smaller, lighter cars are generally not as safe as larger, heavier cars. Large vehicles have longer hoods and bigger crush zone
23、s, which gives them an advantage in frontal crashes. In studies conducted by the Insurance Institute for Highway 1. Adjusted to 2015 dollars Safety (IIHS), a heavier vehicle will typically push a lighter one backward during the impact. As a result, less force will be placed on the occupants of the h
24、eavier vehicle and more on those in the lighter vehicle, according to IIHS. Historically, the rates of driver deaths per million registered vehicles have been higher for the smaller and lighter vehicles. Although aluminum reduces weight in larger vehicles, and the overall weight of the vehicle is re
25、duced enough to increase fuel efficiency to meet the future federal guidelines, the vehicles would retain a weight advantage in a collision. The addition of aluminum or hybrid aluminum/ iron materials would also lower the center of mass for these types of vehicles because steel would remain a major
26、component of the chassis. A lower center of mass relative to height would lower the center of gravity, make a more stable vehicle, and reduce instances of rollover. Two material options available to reduce weight are carbon fiber composites and aluminum. Carbon fiber composite materials have migrate
27、d into many vehicles over the past decade. Recent examples are the BMW i3 mostly composite automobile and Lamborghini Veneno Roadster and Sesto Elemento concept car; some of their vehicles contain as much as 80% carbon fiber composite material. Carbon fiber is quite expensive when compared to steel
28、or aluminum, and it resists high-rate manufacturing processes. Additionally, carbon fiber is not recyclable. It works well to provide the light weight and stiffness desired for performance, high-end vehicles but does not translate well when affordable vehicle cost and high-rate production are desire
29、d. Aluminum is one least-cost alternative to reduce weight across all vehicle types. While aluminum is a least-cost alternative material to reduce weight, it is not without transition-to-production challenges for high-rate production across all road vehicle types. Aluminum has been used in cars for
30、many years in limited applications on body parts such as hoods, trunk lids, and tailgates. Some aluminum side panels exist on a few vehicle types. The application of aluminum to hoods, trunk lids, and tailgates represents attached parts that are bolted onto the main structure of the vehicle. The app
31、lication of aluminum when combined with steel and integrated into the main structural components of a vehicle presents a significant design/engineering and manufacturing challenge to an industry deeply rooted in steel. To an industry characterized by factories filled with thousands of robots spittin
32、g sparks as they weld together steel pieces and parts, aluminum is an alien material fraught with unfamiliar manufacturing processes. Aerospace has long recognized the advantages of aluminum to reduce weight while providing a more formable material than steel. The “goodness” of aluminums characteris
33、tics is offset by its need for more complex manufacturing processes and its sensitivity to corrosion and damage during assembly. Aluminum can be welded, and in certain applications traditional welding methods provide a satisfactory joining solution. For most parts and pieces made of aluminum and joi
34、ned to other aluminum 2 or steel parts and pieces, bonding and fastening are the preferred and most prevalent methods. Before the transformation of mostly steel vehicles into mostly aluminum vehicles occurs, new design criteria must be considered and incorporated. Design complexity increases when re
35、placing steel with aluminum, or combining aluminum and steel into a unified assembly. Aluminum is a softer material. Structural components that were formerly steel require considerable redesign to provide the strength, stiffness, and durability necessary to meet vehicle safety and performance requir
36、ements. Simply replacing an aluminum part for a steel part in the bill of material will not work. Complicating the engineering solution for transitioning a vehicle from steel to aluminum or from steel to a steel/ aluminum combined assembly is the joining method. Joining steel-to-steel using automate
37、d welding technology is a well understood manufacturing process with known outcomes within the automotive industry. Transitioning to bonding, fastening, and other means to hold all the vehicle pieces together presents a design and engineering challenge. The proper size, positioning, placement, and p
38、enetration depth of fasteners contribute to the strength, durability, and performance of a vehicle. Trying to simply transfer spot weld positions from a previous process to fastener placement is unacceptable. Also complicating the design and engineering challenge of bonding and fastening aluminum pi
39、eces and parts together are the new manufacturing challenges for access and automation of the new processes required for aluminum integration into the vehicle. Automating the fastener or bonding process is much more complex than automating spot welding. If the bonding process is employed, bond-line
40、placement and assessment criteria have to be included into the vehicle engineering and design. Bonded aluminum strength properties along the bond-line are highly dependent on many factors including material preparation and cleanliness, uniformity of the bond-line, controlled application, voids, and
41、temperature/humidity at time of application. This complicates a historically less-than- pristine steel manufacturing environment. Fastening aluminum structure to other aluminum pieces or to steel adds complexity to the design engineering and manufacturing challenge. Corrosion is the enemy of aluminu
42、m. Aerospace has long known that given the smallest access to entry, corrosion in aluminum will find an opening and propagate. Corrosion in aluminum parts migrates, often in a clandestine way. Many times it remains unseen and continues to degrade the strength of the material until part or assembly f
43、ailure occurs. A fastened- together mostly aluminum vehicle has a thousand places for entry and propagation of corrosion, which can spread rapidly. Each fastener in aerospace, and by extension road vehicles, must be meticulously protected to prevent entry of corrosion. Simulation and modeling to eva
44、luate and predict galvanic corrosion can provide needed information during the design phase to reduce or eliminate the effects of corrosion. Other corrosion inhibitors include various coating applications that provide an effective barrier to moisture penetration to the metal. Manufacturing enhanceme
45、nts such as clean rooms are necessary additions for the preparation and application of coatings and paint to aluminum. Welding options are applicable to eliminate fasteners that are being considered for joining automotive body parts. Friction stir welding was considered long ago to be a viable optio
46、n to replace fasteners on aluminum aircraft. For the aircraft industry, the rapid replacement of aluminum with high-strength carbon fiber composites killed the migration of this type of technology onto the airframes of many of todays airplanes. It remains a viable option to join certain piece parts
47、of automobile bodies as more aluminum makes its way into the road vehicles of tomorrow. Another limitation and design/engineering consideration is aluminums softer material properties. Again, aerospace designers have recognized that the soft and formable properties of aluminum need to be stiffened w
48、hen they are incorporated into areas that require both stiffness and light weight. One way to accomplish stiffness while retaining the desired light weight of an aluminum part is to incorporate a core sandwiched between two pieces of aluminum. A lighter-weight part is produced, but with the added be
49、nefit of stiffness. The inclusion of a core for targeted parts provides the attributes of stiffness combined with light weight where both are needed. New metals are emerging into the mainstream that effectively coalesce iron and aluminum into a hybrid lighter- weight material that provides stiffness beyond a purely aluminum material. Some of these materials are entering production and offer one viable option to a purely aluminum vehicle. They provide stiffness with only a marginal weight penalty. This book will address some innovative solutions to mitigate the challenges of migra
