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A D V A N C E D
M A T E R I A L S
&
P R O C E S S E S | J U N E
2 0 1 5
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EMERGING
PROFESSIONALS
Geopolymers: Alternatives for Sustainable Development
Behzad Majidi, Laval University
In 2013, world cement pro-
duction was approximately 4 bil-
lion metric tons. The process is
highly material and energy con-
suming, with CO
2
emissions at-
tributed to Portland cement pro-
duction alone comprising roughly
8% of global emissions. Thus, high
energy usage and CO
2
emissions
combined with high consumption
of limestone-based raw materials make Portland cement
production unsustainable.
Geopolymers present a promising alternative. In the
1950s, Victor Glukhovsky first introduced alkali-activat-
ed cements, which were then developed, formulized, and
named geopolymers by Joseph Davidovits in the 1970s. To-
tal CO
2
emissions for the production of geopolymer cements
is estimated to be only one-sixth that of Portland cement.
A wide range of natural clays and industrial residues,
such as Tungsten mine residue, red mud, and blast furnace
slag, have been successfully used in the production of geo-
polymers. It is important to note that annual global pro-
duction of red mud exceeds 70 million metric tons and it is
considered one of the most important industrial waste dis-
posal problems. Use of these materials in the production of
geopolymers provides a convenient and economical way to
dispose of these industrial byproducts. In addition to fewer
environmental issues, superior properties of geopolymers
such as high compressive strength, short setting time, fire
resistance, and high resistance to chemical attacks make
them serious alternatives to Portland cement. Several ap-
plications of geopolymer composites have been reported in
the aerospace industry.
A critical question is, “Why does the industry, in particu-
lar the construction industry, have such an inertia to shift to
geopolymer alternatives?” The answer seems to be that Port-
land cement has been in widespread use over the last two
centuries and, therefore, strong knowledge and experience
have been developed about its properties and long-term be-
havior. On the contrary, geopolymer technology is new and a
conservative view to newmaterials exists in industry.
How many more years can Portland cement sustain
production? Is now the right time to invest in geopolymers?
In any case, a turning point will arrive soon in the indus-
try—a time to go green and switch to a sustainable solution.
HIGHL IGHTS
EMERGING PROFESSIONALS
VOLUNTEERISM
COMMITTEE
Profile of a Voluntee
r
Rob Sparling, Principal, Materials/
Failure Group, Giffin Koerth Foren-
sic Engineering
Rob Sparling is on a mission:
To inspire a new generation of ma-
terials engineers to form strong
communities that improve their
professional and personal lives.
Sparling is a senior engineer for
Giffin Koerth, Canada’s largest fo-
rensic engineering firm. In a field
that provides critical data for legal matters, he sees the
need for both technical and communication skills in the
courtroom, during investigative interviews and in written
reports—and he sees ASM as a venue for improving those
skills.
Sparling joined ASM while studying at McMaster Uni-
versity in Hamilton, Ontario, and attended occasional meet-
ings during his 12 years in aerospace engineering. Now a
senior engineer focused on failure analysis and forensics,
he was inspired to help reinvigorate the Ontario Chapter,
which had dwindled down to about 15 members. “I saw
the need for a sense of community among engineers and a
way to meet people and bounce ideas off each other,” says
Sparling.
He has served as chapter treasurer, vice chair, and
chair—and helped boost membership to about 40 by focus-
ing on university students with events ranging fromwelding
demonstrations to dodgeball games. “Engineers need face-
to-face relationships to solve problems, work on research
papers, or find job openings,” says Sparling. “Students ex-
pect LinkedIn and the Internet to give them a network, but
that’s shortsighted. We need relationships beyond email.
That makes ASMmore important than ever.” He sees ASM as
not only a “premier purveyor of materials information,” but
also the resource that helped him meet and hire two excel-
lent forensic engineers.
Sparling is passionate about recognizing excellence
amongCanadianmaterials engineers andhopes to strength-
en the ASM Canada Council and their annual awards for ex-
cellence. “Professional development is part of who we are
as engineers. With ASM and MSNT, I make it a personal goal
to gain knowledge and stay relevant,” he says.
Majidi
Sparling