7075-T7351 aluminum

Identity: alloy, temper and form

Kaiser's historical bare 7075-T7351 plate table puts a 1.5 in plate at 57 ksi minimum yield and a 2.75 in plate at 49 ksi. The 8 ksi (about 55 MPa) difference comes from thickness bands. Use the current ordered specification and test direction for acceptance. Kaiser historical Table 7.2

7075 is a wrought aluminum–zinc–magnesium–copper alloy. The Aluminum Association's Teal Sheets, revised December 2025, specify zinc at 5.1–6.1%, magnesium at 2.1–2.9%, copper at 1.2–2.0% and chromium at 0.18–0.28% by mass. T7351 is a processing condition, not a separate chemistry designation. Aluminum Association, Teal Sheets, 7075 entry

SAE AMS4078L, revised 10 November 2023, distinguishes 7075-T73 sheet from 7075-T7351 plate and describes solution treatment and overaging. Its public scope covers sheet/plate over 0.039 through 4.000 in thickness. Earlier AMS4078 titles explicitly describe stress-relief stretching for T7351. Preserve the full temper and form rather than shortening either to “7075.” SAE AMS4078L; SAE original AMS4078 publication record

This reference focuses on plate. Rod/bar, extrusions, forgings and clad products require their own standards and property tables. Kaiser's rod/bar datasheet separately lists cold-finished and extruded specifications, illustrating why a common alloy/temper description does not establish product equivalence. Kaiser 7075 rod/bar data, document code KA-RBH-7075-8.10

Order alloy, temper, form, dimensions, applicable specification/edition, surface condition and required inspection evidence. Record orientation and any supplementary corrosion, toughness or nondestructive-testing requirements. An “aerospace” application description does not constitute approval for a specific part.

Strength tradeoff and value status

Kaiser's Sheet Coil & Plate Alloy 7075 Technical Data, marked Rev. 05/06, labels these mechanical values typical:

These values describe that source's typical behavior. They are not guaranteed minima, design allowables or finished-part fatigue data. Kaiser 7075 sheet/plate data, p. 1

Kaiser's handbook reproduces Aluminum Standards and Data 2006 limits. Selected bare 7075-T7351 plate entries are:

These historical entries carry footnotes and specimen requirements. Use the current ordered specification for acceptance. Kaiser handbook, Table 7.2, KA-SP-AA7-1.09

Retain longitudinal, long-transverse and short-transverse orientation relative to the original rolled product. Cutting a blank and rotating the finished drawing does not rotate the grain structure. Keep test direction, specimen location and elongation gauge length with the property record; do not infer untested directions from one tensile coupon.

Stress-corrosion resistance is conditional

The historical handbook's T7351 footnote specifies a short-transverse ASTM G47 test for material 0.750 in and thicker, at 75% of specified minimum yield strength, with lot-acceptance provisions. This is a bounded test condition, not unlimited resistance under every sustained stress, exposure or temperature. Kaiser handbook, Table 7.2 footnote 12, KA-SP-AA10-1.09

Kaiser's comparative table rates T7351 general corrosion C and stress-corrosion B. Its definitions call for protection at least on faying surfaces for C-rated alloys and acknowledge limited short-transverse laboratory failures within B. Neither rating means immunity or a universal service life. Kaiser 7075 comparative characteristics and footnotes

Assess sustained loads, grain direction, residual stress, wet crevices, dissimilar-metal contacts and the protection system. Protect machined edges and holes as required by the design. A corrosion-resistant temper does not eliminate coatings, sealing, drainage or inspection where the assembly specification requires them.

Machining and dimensional stability

Stress-relief treatment does not guarantee zero movement during deep or asymmetric machining. KaiserSelect's aerospace-plate brochure promotes reduced residual stress and improved machining stability as product-specific benefits. Do not assign those claims to every plate sold under the alloy designation. The retrieved brochure shows no printed revision date. KaiserSelect aerospace plate brochure

Plan blank orientation, roughing/finishing sequence, stock allowance and workholding for the actual component. Inspect critical dimensions after operations that release material or introduce heat. A flat incoming plate can still produce a distorted thin wall or pocketed part.

For forming or straightening, qualify the actual thickness, condition, grain direction and tooling. Do not assume T7351 plate behaves like annealed sheet. Any proposed local heating or re-heat-treatment route needs review of final properties, geometry and corrosion condition; the original certificate does not automatically describe the altered region.

Joining, fatigue and service limits

Kaiser rates gas/arc welding and brazing D for T7351, indicating no commonly used developed methods; spot welding receives B, requiring special techniques or application-specific trials. These are process-screening ratings, not approval of a structural welded repair. Kaiser 7075 joining ratings

Evaluate mechanical connections against bearing, net section, fastener loads, fretting and corrosion interfaces. A raw-stock tensile value does not establish connection strength. Changes to joining or repair routes require the applicable design and procedure qualification.

Keep fatigue, fracture toughness and crack growth separate from tensile strength. Obtain properties with the required orientation, specimen and environment, and use the governing design method for load spectrum and inspection intervals. Do not treat a catalog “fatigue strength” as a guaranteed infinite-life limit for a notched, fastened or corroded assembly.

Likewise, room-temperature data does not define continuous-service temperature, fire behavior or compatibility with an arbitrary fluid. Record actual temperature/time history, loading and exposure before selecting the material condition and protection.

Traceable release

Link alloy/temper identity, original product dimensions, orientation, inspection certificate and source edition through cutting and fabrication. Distinguish typical manufacturer values, specification limits, batch results and approved design allowables. Resolve missing test scope, substitutions and changes to thermal or joining history before accepting the finished part.

Related reference

Grades, tempers and conditions