Post on 21-Dec-2015
Phase Equilibria in Ni-P-SnPhase Equilibria in Ni-P-SnC. Schmetterer, J. Vizdal, H. Flandorfer
and H. Ipser
Department of Inorganic Chemistry – Materials Chemistry
University of Vienna
COST 531 Final Meeting, Vienna, May 2007
Technological BackgroundTechnological Background
Ni(P) layers as a contact material:
Protective Ni-layer on Cu substrate
in fact: amorphous Ni(P) layers; P is impurity!
Interaction with Sn-based solders?basic information from phase diagram
ternary phase diagram - and parts of the binaries! - have not yet been investigated
A ssessed N i-Sn phase diagram.
P. Nash and A. Nash, Bull. Alloy Phase Diagrams, 6 (4) (1985) p. 350-358
Ni-Sn Phase Diagram
Binary ConstituentsBinary Constituents
C. Schmetterer et al., accepted for publication in Intermetallics
Ni-Sn DetailsNi-Sn Details
NiNi33Sn phase transitionSn phase transition NiNi33SnSn22 phase transition phase transition
Ni-P and P-SnNi-P and P-Sn
• both systems are currently under investigation• experimental + CALPHAD
A ssessed N i-P phase diagram. Sn-P phase diagram.
• from powders of binary end members (e.g. Ni3Sn) and red P, and Sn
many problems!- embrittlement of quartz capsules- explosion of capsules • samples contained in alumina crucibles
• alloyed in evacuated quartz tubes employing very slow heating, especially at P > 40 at.%
• annealed at 200, 550, 700,850 and 1050 °C
Sample PreparationSample Preparation
Ni2P
Ni3SnNi3Sn2
InvestigationsInvestigationsIn Vienna:
• DTA – not yet fully interpreted
• XRD – isothermal sections
Short Term Scientific MissionShort Term Scientific Missionhost: A. Kodentsov, TUehost: A. Kodentsov, TUe
• Light microscopy + polarized light
• SEM / EDS
• diffusion couples
Phase relations at 550 °CPhase relations at 550 °C
Pseudo-binarySystem Ni2P – Sn?
Ternary phases: Ni2PSn Ni10P3Sn Ni10P3Sn5
Ni10P3Sn8
T4 – new phase?
Phase relations at 700 °CPhase relations at 700 °C
Phase relations at 850 °CPhase relations at 850 °C
Diffusion CouplesDiffusion Couples
Diffusion CouplesDiffusion CouplesNi3Sn / Ni2P
Annealed at 700 °C in vacuum for 100 h
Ni3SnNi3Sn
Ni3 S
n2
Ni3Sn2
??
Ni12P5Ni12P5
Ni2PNi2P
100 µm
Diffusion CouplesDiffusion CouplesSn / Ni2P
Annealed at 200 °C in vacuum for 4 months
SnNi2P
Ni2PSn
Conclusion and OutlookConclusion and OutlookNi-P-Sn:
• first information on phase equilibria
• diffusion couples
Planned investigations:
• continue the phase diagram study
• Calorimetry – enthalpy of mixing, enthalpy of formation
CALPHAD study of the system
AcknowledgementsAcknowledgements
K. Richter, U. Saeed
A. Kodentsov (TU Eindhoven, NL)
H. Schmidt (Dep. f. Physical Chemistry)P. Roussel (Ecole Nationale Superieure de Lille)A. Leineweber (MPI Stuttgart)
Thanks to:
FWF P-16495-N11, COST 531, ELFNET
Thank You for Your Attention