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DEVELOPMENT OF NICKEL-MOLYBDENUM
BASE ALLOYS
H. lnouye T. K. Roche
The available supply of HastelIoy B and W
tubing was prepared by redrawing tubing formed
from welded strip, and it is not of high quality.
Since these alloys are characterized by high-
temperature strength and resistance to fused-salt
corrosion, a source of seamless tubing is desired,
and therefore considerable effort has been devoted
to the study of extrusion techniques for the pro-
duction of seamless tubing of these Hastelloys
and other related alloys.
Extrusion of Hastelloy W
Early attempts to extrude tube blanks of
Hastelloy W failed. In these experiments forged
billets canned in lnconel were extruded at 2050
and 21OCf'F at an extrusion ratio of 7:1. Severe
fracturing of the tubing occurred during the ex-
trusion process as a result of melting. An
excessive temperature rise as a result of the rapid
deformation of the material is believed to have
caused the difficulty. Recently this alloy was
successfully extruded under conditions identical
to those used earlier, as listed below, except for
the extrusion temperature and rate:
5iI let
Billet size
Forged Hastelloy W canned in Inconel
3 in. OD, 1k in. ID, 3 in. long
3.3. FABRICATION RESEARCH
J. H. Coobs
PERIOD ENDlNG JUNE 10, I956
the 2050 and 21OOOF used for the unsuccessful
extrusions. It was concluded from this work that
Hastelloy W could be extruded on a laboratory
scale by raising the extrusion temperature and
lowering the extrusion rate to allow time for the
heat generated in the work to dissipate to the
surroundings. The successful and unsuccessful
tube-blank extrusions are illustrated in Fig. 3.3.1.
Extrusion of Hastelloys 8, W, and X
on a Commercial Scale
An experiment was performed at the Huntington
Works of the International Nickel Company on
March 27, 19%, to determine the feasibility of
producing tube blank extrusions of Hastelloys B,
W, and X on a commercial scale. The experiment
was carried out as a cooperative effort between
the Oak Ridge National Laboratory, the Inter-
national Nickel Company, and the Haynes Stellite
Company.
Forged and machined billets of the Hastelloys
were prepared by the Haynes Stellite Company.
Based upon extrusion experience on a laboratory
scale at ORNL, as described above, a schedule
was prepared for the extrusion of the Hastelloy B
billets. Since small tube blanks had been prepared
successfully by using a slow extrusion rate at
2200°F, it was proposed that these larger billets
. .
be extruded at as slow a rate as practical. The
extrusion temperature could be lower, of course,
because of the larger size of the billet. The
results of the Hastelloy B extrusions, which are
ummarized in Table 3.3.1, were reported to ORNL
y the International Nickel Company upon com-
ent. The actual extruded
stelloy B are shown in Figs.
elloy W and X billets were not
der the direction of ORNL, the fabri-
se alloys is of interest to the overs11
am. The available results
presented in Table 3.3.2.
al conclusions have been
the extrusion of 6,9-in.-OD, 10ts
of Hastelloys B, W, and X:
The extrusion temperature of 2200OF used for 1. Forged billets of Hastelloys B, W, and X can
the successful extrusion was an increase over be successfully extruded to tube blanks.
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