Heat treatable aluminium alloys Precipitation hardening to increase strength 2XXX

140 Pages·2015·5.5 MB·English

aluminium technologies
24.11.2015
Tentative program
● Presentation of HW assignments will start on
December 22nd.
● There will be 5 presentations on
December 22nd
December 29th
January 5th
● Each presentation is expected to last 25 minutes.
● There will be an additional 5 minutes for the
discussion of presentations.
Comparison of casting processes
● Elongation levels of conventional pressure die
casting parts are limited. Hence, pressure die
cast component are not suitable for safety
critical parts.
● Other casting methods that use even higher
pressures, such as squezze and semi-solid casting
have been commercialized in recent years.
● High strength together with elongations much
higher than %10 have been obtained.
Primary and secondary alloys
● Primary alloys are produced by adding alloying
elements to pure aluminium.
● Secondary alloys, on the other hand, are produced
from recycled metal at much lower costs.
● Recycled material is almost always contaminated
with iron.
● Secondary alloys thus contain high levels of Fe
and other impurities. Fe has a negative effect on
castability and ductility and other properties.
● The Fe content must be controlled to a minimum
for these reasons.
Primary and secondary alloys
● The only exception to a low-Fe level is pressure
die casting alloys.
● In sand and permanent mold casting, for
applications that require high ductility, Fe must
be controlled below < 0.20 %. This actually
means primary alloy.
● Fe may be higher when ductility is not critical.
● When castability and machinability are important
Fe can be as high as %0.5 and even higher.
Secondary aluminium alloys can be used in such
cases.
casting alloy designations
Aluminum casting alloys are numbered in accordance
with a 3 digit-plus-decimal designation in order to
identify major alloying elements (and some alloy
combinations).
The digit following the decimal in each alloy number
indicates the form of product.
“0”: the chemistry limits applied to an alloy casting.
“1”: the chemistry limits for ingot used to make the
alloy casting.
“2”: the chemistry limits for ingot are different
(typically tighter).
casting alloy designations
Generally, the XXX.1 designation indicates the ingot
is supplied as a secondary product (e.g., remelted
from scrap),
whereas the XXX.2 designation suggests the ingot is
produced from primary aluminum.
Some alloy names are preceded by a letter so as to
distinguish between alloys that differ only slightly in
percentages of impurities or minor alloying elements
(e.g., 356.0, A356.0, B356.0 or F356.0).
Sand casting alloys
Si Fe Cu Mn Mg Cr Ni Zn Sn Ti
201.0
0.10 0.15 4.0–5.2 0.20–0.50 0.15–0.55 ... ... ... ... 0.15–0.35
204.0
0.20 0.35 4.2–5.0 0.10 0.15–0.35 ... 0.05 0.10 0.05 0.15–0.30
242.0
0.7 1.0 3.7–4.5 0.35 1.2–1.8 0.25 1.7–2.3 0.35 ... 0.25
295.0
0.7–1.5 1.0 4.0–5.0 0.35 0.03 ... ... 0.35 ... 0.25
319.0
5.5–6.5 1.0 3.0–4.0 0.50 0.10 ... 0.35 1.0 ... 0.25
328.0
7.5–8.5 1.0 1.0–2.0 0.20–0.6 0.20–0.6 0.35 0.25 1.5 ... 0.25
355.0 4.5–5.5 0.6B 1.0–1.5 0.50B 0.40–0.6 0.25 ... 0.35 ... 0.25
356.0 6.5–7.5 0.6B 0.25 0.35B 0.20–0.45 ... ... 0.35 ... 0.25
443.0
4.5–6.0 0.8 0.6 0.50 0.05 0.25 ... 0.50 ... 0.25
512.0
1.4–2.2 0.6 0.35 0.8 3.5–4.5 0.25 ... 0.35 ... 0.25
514.0
0.35 0.50 0.15 0.35 3.5–4.5 ... ... 0.15 ... 0.25
520.0
0.25 0.30 0.25 0.15 9.5–10.6 ... ... 0.15 ... 0.25
535.0
0.15 0.15 0.05 0.10–0.25 6.2–7.5 ... ... ... ... 0.10–0.25
Sand casting alloys
Si Fe Cu Mn Mg Cr Ni Zn Sn Ti
0.20 0.8 0.20 0.40–0.6 1.4–1.8 0.20– ... 2.7–3.3 ... 0.25
705.0
0.40
0.20 0.8 0.20 0.40–0.6 1.8–2.4 0.20– ... 4.0–4.5 ... 0.25
707.0
0.40
0.15 0.50 0.35– 0.05 0.6–0.8 ... ... 6.0–7.0 ... 0.25
710.0
0.65
0.30 0.50 0.25 0.10 0.50–0.65 0.40–0.6 ... 5.0–6.5 ... 0.15–
712.0
0.25
713.0
0.25 1.1 0.40–1.0 0.6 0.20–0.50 0.35 0.15 7.0–8.0 ... 0.25
0.15 0.15 0.10 0.10 0.8–1.0 0.06–0.2 ... 6.5–7.5 ... 0.10–
771.0
0.20
850.0
0.7 0.7 0.7–1.3 0.10 0.10 ... 0.7–1.3 ... 5.5–7.0 0.20
851.0
2.0–3.0 0.7 0.7–1.3 0.10 0.10 ... 0.30–0.7 ... 5.5–7.0 0.20
852.0
0.40 0.7 1.7–2.3 0.10 0.6–0.9 ... 0.9–1.5 ... 5.5–7.0 0.20
Permanent mold casting alloys
Si Fe Cu Mn Mg Cr Ni Zn Sn Ti
204.0
0.20 0.35 4.2–5.0 0.10 0.15–0.35 ... 0.05 0.10 0.05 0.15–0.30
208.0
2.5-3.5 1.2 3.5-4.5 0.50 0.10 … 0.35 1.0 … 0.25
222.0
2.0 1.5 9.2-10.7 0.50 0.15-0.35 … 0.50 0.8 … 0.25
242.0
0.7 1.0 3.7–4.5 0.35 1.2–1.8 0.25 1.7–2.3 0.35 ... 0.25
296.0
2.0–3.0 1.2 4.0–5.0 0.35 0.05 ... 0.35 0.50 ... 0.25
308.0
5.0-6.0 1.0 4.0-5.0 0.50 0.10 … … 1.0 … 0.25
319.0
5.5–6.5 1.0 3.0–4.0 0.50 0.10 ... 0.35 1.0 ... 0.25
332.0
8.5–10.5 1.2 2.0–4.0 0.50 0.50–1.5 … 0.50 1.0 ... 0.25
333.0
8.0-10.0 1.0 3.0-4.0 0.50 0.05-0.50 … 0.50 1.0 … 0.25
336.0
11.0-13.0 1.2 0.50-1.5 0.35 0.7-1.3 … 2.0-3.0 0.35 … 0.25
354.0
8.6-9.4 0.20 1.6-2.0 0.10 0.4-0.6 … … 0.10 0.20
355.0 4.5–5.5 0.6B 1.0–1.5 0.50B 0.40–0.6 0.25 ... 0.35 ... 0.25
356.0 6.5–7.5 0.6B 0.25 0.35B 0.20–0.45 ... ... 0.35 ... 0.25