An Example of part of a Worksheet Addressing Student Difficulties with Phase Diagrams
1
Research and development of group- work “tutorials” for the introductory materials course. Rebecca Rosenblatt, Andrew Heckler, Katharine Flores An Example of part of a Worksheet Addressing Student Difficulties with Phase Diagrams Draw pictures of the microstructure of this Copper- Silver cool the solution. At 24% Ag At 72% Ag At 97% Ag Two Examples of Student Difficulties with Phase Diagrams At point b2 what is the fraction of the alloy that is α? {picture to the right was given.} 19% a) 6% 48% b) 25% 11% c) 28% 21% d) 72% 2% e) 94% Which of the following sketches best illustrates the microstructure that will develop when the 30 wt% Ag alloy is cooled slowly from 1000°C to 250°C? (Refer to the above diagram) 9% a) A 73% b) B 7% c) C 11% d) D Initial Focuses: 1. Development of a Materials Concept Inventory 2. Development and evaluation of tutorial like group- work activities for recitations. 3. Assessment and Improvement of the Teaching Assistants’ content and pedagogical knowledge. MSE 205: Introduction to Materials Science • Approx. 500 students/year • Freshmen – seniors • Primarily engineering majors • Approx. 10% of class are materials science majors An Example of part of a Worksheet Addressing Student Difficulties with Strength and Plastic Deformation. 1. How is the strength of a metal defined? (Please give description that a 2 nd year engineering student who has not taken this class yet would understand.) 2. What is the difference between yield strength and tensile strength? 3. A tensile stress is applied to a metal bar such that is deforms plastically. Draw a sample of atoms in the bar a) Before deformation b) During deformation while under stress c) After the stress is released 4. After the stress is released, is the bar’s volume different than before being deformed? Explain. 5. Does the density change after plastic deformation? If so, how? Identification of discipline specific “misconceptions” Faculty and student interviews Classroom observation Student testing Targeted curriculum Interactive materials Multiple contexts Iterative, spiraling Student-centered Assessment Conceptual Understanding Problem Solving Ability Knowledge Breadth Result: Improved student learning Development Cycle in Education Research Two Examples of Student Difficulties with Mechanical Properties A metal is permanently elongated by an applied tensile stress, and then the stress is removed. Which of the following is true? a) Atoms are rearranged compared to before the elongation. b) The atomic bonds are stretched compared to before the elongation. c) Both a) and b) will happen The two pieces shown below were cut from the same piece of metal. Nothing else has been done to the pieces. Compare the yield strength of the pieces. d) A has a higher yield strength than B e) B has a higher yield strength than A f) A and B have the same yield strength A (A and B have equal heights) B Non-Rec. questions (15) Rec. questions (7) 0 0.2 0.4 0.6 0.8 0.700000000 000001 0.547 0.769000000 000004 0.752000000 000004 Did not attend Recitation (N= 115) Au 2009 Final Exam Scores Show a Positive Effect of Recitation Attendance 29% 11% 60% 58% 11% 31% Microstructure B b a Microstructure A a b Microstructure C a b Microstructure D b a Conclusions: • Use of group-work “tutorials” in the Materials Science course does not lead to better attendance in the none mandatory recitations. • Students who attend did even better on the recitation related questions on the final exam than would be expected from those students over all better performance. • Weekly TA training sessions are important to remind and fill in any content knowledge that is necessary for the Integrated research on emergent materials and phenomena in magnetoelectronics IRG-1: Towards Spin-Preserving, Heterogeneous Spin Networks -50 0 50 1 7 dI/dV (pA /m V) V o ltag e (m V) 10 Å a -TC N E a-TC N E STM images of TCNE, tetracyanoethylene (C6N4), on a Cu(111) surface acquired at low temperatures (5 K or -268 °C). By applying a voltage pulse with the STM tip, it is observed that a single TCNE molecule can be reversibly switched between the nonmagnetic α and magnetic δ states. This kind of multistability has recently been proposed for massively parallel computing on the nanometer scale. -- Arthur Epstein and Jay Gupta Graphene Fabrication of graphene spin valves with ultrathin magnesium oxide (MgO) tunnel barrier. This breakthrough enables the development of a graphene spin computer, that can integrate logic and memory for much greater computing power. --Roland Kawakami IRG-2: Double Perovskite Interfaces and Heterostructures Mn Ru O Chem. Mater. 19 [26], 6451- 6458 Discovering new magnetic properties in Ca 2 MnRuO 6 , where the Mn and Ru ions order ferrimagnetically at room temperature, despite the fact that they are randomly distributed in the lattice. Chemically substituting La 3+ for Ca 2+ tunes the conductivity from metallic to semiconducting while retaining the ferrimagnetism. Understanding this unique behavior may hold important clues for magnetism and half-metallic transport in the broader class of double perovskites. –Patrick Woodward Depositing highly ordered, single crystalline films of Sr 2 FeMoO 6 that retain their magnetism to temperatures over 227°C. Scanning transmission electron microscope image of an Sr 2 FeMoO 6 film Ordered double perovskites, such as Sr 2 FeMoO 6 , are among the very few materials that allow electrons of one spin direction to move through them as though they were passing through a normal metal, while blocking electrons of the opposite spin. --Hamish Fraser and Fengyuan Yang Sr Fe Mo O Double perovskite lattice Seed Funding: This program complements the IRGs, and it is aimed at supporting new materials research ideas with the potential for transformative impact on science and technology. Magnetic Tweezers Magnetic nanowire Developing micon- and nanometer magnetic particles for single biomolecule torque and force measurements. Providing new molecular insight into gene expression, replication and repair. – Michael Poirier Effect size 0.4 Effect size 1.0 An NSF Materials Research Science and Engineering Center (MRSEC) Supported under NSF Award Number DMR-0820414
description
29%. 58 %. 11%. 11%. 31 %. (A and B have equal heights). B. 60%. A. b. b. b. a. a. a. Microstructure D. Microstructure C. Microstructure B. b. a. Microstructure A. Research and development of group-work “tutorials” for the introductory m aterials c ourse . - PowerPoint PPT Presentation
Transcript of An Example of part of a Worksheet Addressing Student Difficulties with Phase Diagrams
Research and development of group-work “tutorials” for the introductory materials course.
Rebecca Rosenblatt, Andrew Heckler, Katharine Flores
An Example of part of a Worksheet Addressing Student Difficulties with Phase Diagrams
Draw pictures of the microstructure of this Copper- Silver alloy as you slowly cool the solution.
At 24% Ag
At 72% Ag
At 97% Ag
Two Examples of Student Difficulties with Phase Diagrams
At point b2 what is the fraction of the alloy that is α? {picture to the right was given.} 19% a) 6% 48% b) 25% 11% c) 28% 21% d) 72% 2% e) 94%
Which of the following sketches best illustrates the microstructure that will develop when the 30 wt% Ag alloy is cooled slowly from 1000°C to 250°C? (Refer to the above diagram) 9% a) A 73% b) B 7% c) C 11% d) D
Initial Focuses:1. Development of a Materials Concept Inventory 2. Development and evaluation of tutorial like group- work activities for recitations.3. Assessment and Improvement of the Teaching Assistants’ content and pedagogical knowledge.
MSE 205: Introduction to Materials Science• Approx. 500 students/year• Freshmen – seniors• Primarily engineering majors• Approx. 10% of class are materials science
majors
An Example of part of a Worksheet Addressing Student Difficulties with Strength and Plastic Deformation. 1. How is the strength of a metal defined? (Please give description that a 2nd year engineering student who has not taken this class yet would understand.) 2. What is the difference between yield strength and tensile strength? 3. A tensile stress is applied to a metal bar such that is deforms plastically. Draw a sample of atoms in the bara) Before deformation b) During deformation while under stress c) After the stress is released 4. After the stress is released, is the bar’s volume different than before being deformed? Explain. 5. Does the density change after plastic deformation? If so, how?
Identification of discipline specific “misconceptions”
Faculty and student interviewsClassroom observation
Student testing
Targeted curriculumInteractive materials
Multiple contextsIterative, spiralingStudent-centered
AssessmentConceptual Understanding
Problem Solving AbilityKnowledge Breadth
Result: Improved student learning
Development Cycle in Education Research
Two Examples of Student Difficulties with Mechanical Properties
A metal is permanently elongated by an applied tensile stress, and then the stress is removed. Which of the following is true?
a) Atoms are rearranged compared to before the elongation.
b) The atomic bonds are stretched compared to before the elongation.
c) Both a) and b) will happen
The two pieces shown below were cut from the same piece of metal. Nothing else has been done to the pieces. Compare the yield strength of the pieces.
d) A has a higher yield strength than Be) B has a higher yield strength than Af) A and B have the same yield strength
A (A and B have equal heights)B
Non-Rec. questions (15) Rec. questions (7)0
0.2
0.4
0.6
0.8
0.700000000000001
0.547
0.769000000000004 0.75200000000
0004
Did not attend Recitation (N= 115) Attended Recitation (N = 45)
Au 2009 Final Exam Scores Show a Positive Effect of Recitation Attendance
29%
11%
60%
58%
11%
31%
Microstructure B
b
a
Microstructure A
a
b
Microstructure C
a
b
Microstructure D
b
a
Conclusions:• Use of group-work “tutorials” in the Materials Science course does not lead to better attendance in the none mandatory recitations.
• Students who attend did even better on the recitation related questions on the final exam than would be expected from those students over all better performance.
• Weekly TA training sessions are important to remind and fill in any content knowledge that is necessary for the “tutorial” and to inform the TAs of areas of difficulty that the students will have.
Integrated research on emergent materials and phenomena in magnetoelectronics
IRG-1: Towards Spin-Preserving, Heterogeneous Spin Networks
-10
-5
0
5
Ene
rgy
(eV
)
-50 0 501
7
dI/d
V (p
A/m
V)
Voltage (mV)
Co(TCNE)
10 Å
a
-TCNEa-TCNE
LUMO
Cu2N
A B
STM images of TCNE, tetracyanoethylene (C6N4), on a Cu(111) surface acquired at low temperatures (5 K or -268 °C).
By applying a voltage pulse with the STM tip, it is observed that a single TCNE molecule can be reversibly switched between the nonmagnetic α and magnetic δ states.
This kind of multistability has recently been proposed for massively parallel computing on the nanometer scale. --Arthur Epstein and Jay Gupta
Graphene
Fabrication of graphene spin valves with ultrathin magnesium oxide (MgO) tunnel barrier.
This breakthrough enables the development of a graphene spin computer, that can integrate logic and memory for much greater computing power. --Roland Kawakami
IRG-2: Double Perovskite Interfaces and Heterostructures
Mn
Ru
O
Chem. Mater. 19 [26], 6451-6458
Discovering new magnetic properties in Ca2MnRuO6, where the Mn and Ru ions order ferrimagnetically at room temperature, despite the fact that they are randomly distributed in the lattice.
Chemically substituting La3+ for Ca2+ tunes the conductivity from metallic to semiconducting while retaining the ferrimagnetism.
Understanding this unique behavior may hold important clues for magnetism and half-metallic transport in the broader class of double perovskites. –Patrick Woodward
Depositing highly ordered, single crystalline films of Sr2FeMoO6 that retain their magnetism to temperatures over 227°C.
Scanning transmission electron microscope image of an Sr2FeMoO6 film
Ordered double perovskites, such as Sr2FeMoO6, are among the very few materials that allow electrons of one spin direction to move through them as though they were passing through a normal metal, while blocking electrons of the opposite spin. --Hamish Fraser and Fengyuan Yang
Sr
Fe
Mo
O
Double perovskite lattice
Seed Funding: This program complements the IRGs, and it is aimed at supporting new materials research ideas with the potential for transformative impact on science and technology.
Magnetic Tweezers
Magnetic nanowire
Developing micon- and nanometer magnetic particles for single biomolecule torque and force measurements. Providing new molecular insight into gene expression, replication and repair. –Michael PoirierEffect size 0.4 Effect size 1.0
An NSF Materials Research Science and Engineering Center (MRSEC) Supported under NSF Award Number DMR-0820414
