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Steelmaking Team
4/22/14
• Angelica Moore • Devin Rowe
• Thomas Simpson• Justin Twohy
Main Goal and Customers
• To produce 10 lbs of steel/cast iron with each of the following carbon percentages by weight:
< 0.81.5-2.5> 3.0
• Any iron oxide may be used• The customers are future sword-manufacturing
design teams and the MET department
Iron Oxide Source
Hematite Pellets were crushed with a ¼ inch gap in the rollerthe first pass and then about 1/16 - 1/8 inch the second and final pass through the rolling crusher.
Crucible Selection
Inner-Diameter: 27.9cm
Height: 28.6cm
How to Accomplish1.Reduce hematite pellets with coke
2.Based on a mass balance of iron and carbon, estimate needed ratios to Create 10 pounds of the carbon steel ( <0.8 wt% C), high carbon steel/cast iron (1.5-2.5 wt% C), and the high carbon (>3 wt% C) cast iron
3. Perform metallography/ analysis to determine the above goals were met
4. Normalize and decarburize as necessary.
What is Left To Do
• Week (4/22)– Attempt to decarburize and normalize the metal from Batch 2 for use in forging a blade. Continue work on final report and electronic binder.
• Week (5/3)– Finish and submit final report and electronic binder
Problems EncounteredPressure loss• Continual gas expansion• Temperature drops at end of
run• Inefficient gas use• A heated blanket was used to
offset the temperature slightly
Air Preheater• Large open flame • Burns wood too quickly• Unsteady temperatures• Oak charcoal used in later runs, produced higher and
more constant temperatures.
Problems Encountered Continued
Faulty Thermal Couple• Ice water was warmer than the
furnace• A short was found and corrected
O2 Sensor cracked• Thermal shock brought on by improper
heating.• Nichrome wire melted (Melting point
1400oC)• One data point measured but probably
flawed
Problems Encountered ContinuedDifficulties Pouring
First Crucible (right)• First run metal was not hot enough and we were
unprepared.• Inaccurate assessment of crucible’s integrity led us
to destroy it to free the metallic iron product.
Second Crucible (left)• Smaller and thinner than first, though advertised the
same and purchased from same link. (Ebay go figure)• Thinner walls contributed to a leak in the crucible.• Half of the last batch of iron product was at the
bottom of the caster. Later recovered
Accomplishments• 3 Batches of steel/iron product with different carbon percentages were
successfully smelted.
• Total amount produced, approximately 26 pounds.
• About 6X more than the previous team, who were the only Steelmaking team besides us to reduce iron.
Accomplishments ContinuedBatch 1• Approximate weight: 11lbs• Our attempt at > 3.0 wt%
carbon.• The amount of coke used forced
this batch to be completed in two runs,
• Unable to pour, destroyed first crucible to liberate it.
• Very porous large amounts of unused coke imbedded in it.
• Too hard to cut but brittle enough to chip off a sample.
Metallography (next slide)• Large amounts of pearlite and
Cementite.• Determined to be above 3.0 wt% C
Accomplishments ContinuedBatch 2• Approximate weight: 7.3lbs• Our attempt at < 0.8 wt% carbon.• Only successful pour.• Much less porous than previous batch.• Soft enough to cut a sample.• Attempts to homogenize through forging
failed. Possibly was not hot enough.
Metallography• Large amounts of voids in metal• Largely pearlite, small amounts of ferrite
and cementite grains.• Estimated to be between .76-.90 wt% C
Accomplishments ContinuedBatch 3• Approximate weight: 7.7lbs• Our attempt at 1.5-2.5 wt% carbon.• Hole in crucible lead to only a partial
pour.• Molten iron spilled over a small area
in front of the caster as well. Most recovered later. One of the cooled pools of spilt molten metal used for sample.
• More porous than Batch 2 but less than Batch 1.
Metallography• Large amounts of voids in metal• Largely pearlite with veins of
cementite a grain boundaries.• Estimated to be above 0.90 wt% C
What We Would Do Differently• Perform practice runs to make sure our equipment
worked with our crucibles/ figure out the best fuel to air ratio
• Use a mixture of charcoal and coke as fuel• Start trying to smelt iron/steel product earlier• Kill the steel with ferromanganese or ferrosilicon• Attempt to make a suitable crucible out of castable
refractory material• Normalize our ingots before working• Shield the O2 sensor adequately • Make more s’mores• Keep better records of fuel to air ratio before the gauge
stuck
Secretly We Are Also The S'mores Making Team
We are now open for
Questions or Comments