Indeed, they’ve already aided successful
missions. Two of Morgan Advanced Materials’
braze alloys, RI-46 and RI-49, were specifically
engineered and used by NASA on the Space
Shuttle Main Engine, also known as the RS25.
RI-46 specifically was developed as a
replacement for the existing Nioro braze
alloy, which is comprised of 82/18 Au/Ni
(gold/nickel). RI-46 contains much less gold,
adding in copper and manganese instead.
This helped make the braze alloy significantly
less dense and provided crucial weight
savings, but also still operable from a wide
range of temperatures, between -240°C to
700°C (-400°F to 1292°F).
These alloys have not only been critical
for past space missions, but also for future
missions. RI-46 and RI-49 have been adopted
for NASA’s Space Launch System (SLS), a
vehicle that is planned to take a crewed
mission to Mars.
As alluded to already, developing new braze
alloys is as much about performance as well
as sustainability.
THE NEED FOR NON-PRECIOUS
ALLOYS
It needs no mention that space exploration
is a costly exercise. According to NASA, the
average cost to launch a Space Shuttle is
$450 million per mission. The Space Shuttle
Endeavour, the orbiter built to replace the
Space Shuttle Challenger, cost an eye-
watering $1.7 billion USD.
Bringing costs down is clearly required to
keep space missions feasible. One key part
of cost reduction is in reducing the use of
precious metal braze alloys.
Precious metals like gold and palladium are
becoming increasingly scarce. Of course, the
cost of producing alloys from these precious
metals is also increasing as a result.
However, there can be a reluctance to come
away from using precious metal alloys. Years
of research, development and data means
these alloys are tested and reliable. When
dealing with missions and equipment that
run into the hundreds of millions of dollars
and, more importantly, the lives of crew
members, reliability becomes an overarching
objective, and failures must be prevented.
To solve this issue, Morgan’s Braze Alloys
business has been researching and
developing non-precious metal alloys over
many years. As seen from the RI-46 and RI-49
alloys, these solutions are just as strong
as their equivalent high precious-metal
counterparts, but at a fraction of the cost.
Non-precious metal alloys can be made from
metals like nickel, chromium, and cobalt.
Their success has already been seen in the
aerospace sector, and now research is being
pioneered into making them fit for going into
orbit and beyond.
SPACE, FOR ALL TO ENJOY
Space travel is not just for highly trained
astronauts and public benefit, there is also
a growing commercial aspect. Satellite TV
and radio has already been mentioned, but
billionaire entrepreneurs such as Richard
Branson and Elon Musk have also been
pioneering private space travel. The hope is
that civilians might one day be able to enjoy
outer space as well, albeit for potentially high
prices.
Achieving this dream is of course hinged on
safety and reliability, given that lives will be
at stake. The key to improving these factors
is being able to place sensors as close as
possible to the spacecraft’s engine.
By enabling sensors to be placed as close as
possible to the spacecraft’s engine, mission
control and crew can then accurately
read and measure data and output. This
includes fuel efficiency, temperature, gas
flow and monitoring for fire detection or
abnormalities. If these sensors are placed
too far away from the engines, then data
readings become inaccurate and missions
can be compromised.
Recent news highlights why sensor
technologies are critical, as a two-man
space crew had to abort their flight to the
ISS after a post-rocket launch failure. The
Soyuz spacecraft started to experience failure
119 seconds into the flight, and seemingly,
problems were reported by the crew first,
not by mission control. The crew described
feelings of weightlessness, an indication of
a problem during that stage of the flight.
Luckily, they aborted, ejected their capsule
from the rocket, and returned safely to Earth.
While the cause is of the failure is still to
be identified at time of writing, clearly,
such a situation should not be happening.
Any problems should be picked up by
mission control, and not be reliant on crew
judgement.
Issue 38 PECM
25