Furukawa-Sky Aluminum

NewNew Products
Products

Thick Plate of Aluminum Alloys for Aircraft

1.

INTRODUCTION

Furukawa-Sky Aluminum is supplying aluminum rolled
products of high quality to a broad range of industries.
Especially in the field of thick plates for aircraft, theCompany maintains the top market share taking advantage of the nation’s foremost thick plate production facilities at its Fukui Works.
The Fukui Works acquired the certification of AS9100 in
April 2005 for the first time in the domestic light metalrolled products industry, and we were also registered in
the internationally unified database system OASIS (Online
Aerospace Supplier Information System) of IAQG
(International Aerospace Quality Group). AS9100 is formulated as an internationally viable standard, and standsfor American Aerospace Quality Group of IAQG9100, theinternationally unified standard of IAQG’s quality management system. Compared to the ISO9001 international
standard for quality management, it involves additional
requirements specific to aerospace industry such as functions, performance, and reliability and safety guarantees
of aerospace products. This certification acquisition has
brought about an international recognition of ourCompany as a manufacturer of aluminum thick plates foraircraft, so that more foreign aircraft manufacturers havebegun to use our thick plates for aircraft in their airframes.

Requirements inaerospace ﬁeld

AS9100 orJIS Q9100

Manufacturing of airframes for aircraft involves: 1) certification of quality management system, 2) accreditation ofmaterials by airframe manufacturer, and 3) accreditationof special processes including heat treatment in material
manufacturing and nondestructive testing for quality
assurance. Especially for special processes, as shown in
Figure 1, it is indispensable to have accreditation from aninternational accreditation organization Nadcap (NationalAerospace and Defense Contractors Accreditation
Program), and accordingly, the Fukui Works acquired thecertification in August 2006. Also, our Oyama Forging
Plant has already acquired the certification.
Now that Furukawa-Sky Aluminum is the only manufacturer of aluminum rolled products in this country that has
acquired Nadcap accreditation, the observance of themanufacturing conditions in the special processes will beaccredited together with control levels by periodical surveys even after the accreditation acquisition. Table 1
shows the main accreditation status at the Fukui Works.

2.

DEVELOPMENT BACKGROUND

Demands for thick plates for aircraft increased centeringon commercial aircraft in the late 1990s, and the Fukui
Works carried out numerous developments to cope withsuch growing demands. Against this background, thedemand for 7000-series materials --- specifically 7050alloy materials that have high strength and high toughness--- grew rapidly, as the component structures changed
from assembly-type to integrally machined-type with theobjective of airframe lightening and man-hour reduction.
The Fukui Works has been developing technologiesaimed at an integrated system of production from casting
to rolling for 7050-alloy materials. Since this alloy is prone
to crack during ingot cooling, we have accumulated vari-Requirements of ISO9001

Table 1Accreditation status at the Fukui Works.

Alloy / Process

Applicable standard

2024

AMS-QQ-A-250/4

To have acquired an AS9100 or JIS Q9100
certiﬁcation from certiﬁcation organization

2024C

AMS-QQ-A-250/5

7050

AMS4050

To have special processes (ultrasonictesting) managed and maintained

7075

AMS-QQ-A-250/12

7475

AMS4202

Qualiﬁcation for Nadcap

Heat treatment
Nadcap accreditation

Figure 1

Correlation between AS9100 and Nadcap.

Ultrasonic testing

AMS2750
AMS2772
AMS-STD-2154
Nadcap

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Thick Plate of Aluminum Alloys for Aircraftous improvements in terms of ingot form and the application method of cooling water during casting, and ultimately achieved delivery of the mass products to domestic airframe manufacturers in 2002. In 2004, we acquired anaccreditation of Canadian airframe manufacturer
Bombardier Aerospace to begin delivery.

3.

FEATURES

3.1 Materials
Aircraft is required to reduce its weight to ensure flight performance and fuel cost reduction, and this leads to the useof the 2000-series and 7000-series aluminum alloys thestrength of which can be improved through heat treatment.
For example, for the outer airframe panels, 2024C-alloy
plate is used comprising 2024-alloy clad with a 1000series alloy on the surface, and for portions constituting theairframe, 7050- and 7475-alloys are mainly used. Amongthese, 2024C-alloy plate is used, after surface polished togive mirror finish, as an outer panel for commercial passenger aircraft, while 7050- and 7475-alloys are used in avariety of fields including airframes for the Ministry ofDefense. In the aerospace industry, 2000-series alloys areused as a liquid fuel tank stock for the H2A rockets.
These alloys are manufactured using heat treatment tosatisfy the required strength and other properties.

All these processes are the subjects of the Nadcap
accreditation mentioned above, and day-by-day management is strictly exercised.

4.

PRODUCTS SIZE

It is required these days that materials for aircraft be thicker and stronger. Table 2 shows the size of typical productswith the maximum thickness manufacturable.

5.

CONCLUSION

The demand for 7050-alloy with improved property is
increasing as thick plates for new aircraft that is scheduled
to be in operation soon. In response to the requirementsof airframe components manufacturers, we are further promoting research and development in order to supply better materials with higher strength and higher toughness.
For more information, please contact:
Engineering Dept., Furukawa-Sky Aluminum
TEL: +81-3-5295-3781 FAX: +81-3-5295-3761

3.2 Quality Requirements
It is required, to cope with further safety design, that thesematerials have enhanced properties in fracture mechanics
such as stress corrosion resistance and fracture toughness as well as high strength. To this end, all the processes are managed to manufacture high-quality products,
including thorough control of temperature and filtering
capability in the casting process in addition to periodic
checkup of temperature control functions in the heat treatment process. And the products produced by these strictly controlled processes undergo a series of shipping tests
such as strength test, electric conductivity test and K1ctest, in order to guarantee their quality.
3.3 Features in Manufacturing
Unlike aluminum alloys for general purpose, the heat treatment alloys for aircraft mentioned above require numerous
processes such as solution treatment and quenching,residual stress relief, and aging treatment. Two quenching
furnaces have been installed in the Fukui Works, so that it
is possible to solution treat and quench thick plates having
a thickness of 127 mm maximum and a width of 3,000 mmmaximum. The No.2 quenching furnace shown in Figure 2
is a new and powerful machine that went into operation inJanuary 2006. In addition to a hot roughing-down mill thatis the world’s second largest in terms of the maximum rolling width, we have a stretcher having the largest power inthe country, thereby making it possible to manufacture thenation’s largest aluminum thick plates for aircraft.
Moreover, an ultrasonic tester is used to assure that thethick plate products are free from internal defects such as
porosity attributable to casting structures.

Figure 2

No.2 quenching furnace.

Figure 3

Table 2Stretcher.

Size of typical products with the maximum thickness
manufacturable.
Alloy / temper

Typical size (mm)2024C-T3

5 × 2390 × 12000

7050-T7451

127 × 1219 × 3658

7475-T7351

102 × 1219 × 3658

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