Synthesis of Polycarbosilane, Polymer Impregnation Pyrolysis based C SiC Composites and Prototype Development

Suresh Kumar; Raghwesh Mishra; Ashok Ranjan; L.M. Manocha; N. Eswara Prasad

doi:10.14429/dsj.69.13572

Suresh Kumar DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur – 208 013
Raghwesh Mishra DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur – 208 013
Ashok Ranjan DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur – 208 013
L.M. Manocha DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur – 208 013
N. Eswara Prasad DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur – 208 013

DOI: https://doi.org/10.14429/dsj.69.13572

Keywords: Polycarbosilane, SiC fibre, PIP process, C/SiC composites

Abstract

Due to some extraordinary thermo-mechanical properties, silicon carbide is considered one of the best materials used for high temperature applications in defence and aerospace. Polycarbosilane (PCS) has been widely used as SiC precursor. This paper describes the research and development work undertaken to establish the technologies for synthesis and characterisation of PCS, fabrication process and characterisation of Carbon fibre reinforced SiC matrix (C/SiC) composite laminates and shaped articles. The molecular weight and softening point of the PCS was found to be 1400-1800 Mn and 140-150 °C respectively. Flexural stress of the unidirectional (UD) C/SiC composites and bidirectional (2D) C/SiC composites was found to be 400-450 MPa and 300-350 MPa respectively. Tensile stress of the 2D C/SiC composite was found to be around 200 MPa. Coefficient of thermal expansion and thermal diffusivity of the 2D C/SiC composites at RT- 1000 °C were found to be in range of 0.3-2.2×10-6/ °C and 32-6 mm2/s respectively. The fabrication process developed for the UD and 2D C/SiC composites using the indigenous PCS has been also demonstrated to fabricate typical size divergent rocket nozzle and hot structure. Fabrication process of the SiC fibre has also been described in brief.

Author Biographies

Suresh Kumar, DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur – 208 013

Dr Suresh Kumar, received MTech and PhD in Chemical Engineering from IIT Delhi. Presently working as Scientist ‘F’ and Head, Directorate of Ceramics and CMCs at DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur. His current research interest includes process modifications and products of SiC fibres, C/SiC, SiC/SiC, RBSC, UHTCs and improved ablative materials. He has designed the process for SiC fibres, C/SiC composites, fabricated and characterised the C/SiC composites and developed the first draft of the manuscript.

Raghwesh Mishra, DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur – 208 013

Mr Raghwesh Mishra received his BSc and MSc (Organic Chemistry Spl.) from CSJM University, Kanpur. Presently working as Scientist ‘E’ at DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur. His current research interest includes high temperature ceramic materials for thermal ablation and insulation.

Ashok Ranjan, DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur – 208 013

Dr Ashok Ranjan received his MSc (Chemistry) and PhD (Organometallics) from Lucknow University, Lucknow. He served in DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur. His research interest includes the development of inorganic polymers like polysilanes, polycarbosilane, polysiloxane, polyphosphazenes and their applications.

L.M. Manocha, DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur – 208 013

Prof. Lalit Mohan Manocha worked as a DRDO Raja Ramana Distinguished Fellow at DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur. He has been working for forty years at National/International organisations in the area of advanced materials like solid and porous carbons, carbon fibres, carbon/carbon composites, ceramic matrix composites, nanomaterials and has developed technology for same.

N. Eswara Prasad, DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur – 208 013

Dr N. Eswara Prasad received his BTech (1985) and PhD (1993) in Metallurgical Engineering from IIT, BHU and is currently serving as Outstanding Scientist and Director, DRDO-Defence Materials and Stores Research and Development Establishment, Kanpur. His prolific research has resulted in over 300 research articles in peer-reviewed journals, conference proceedings and technical reports, apart from authoring or editing 15 books, 32 book chapters, 90 confidential reports, 10 policy papers for MoD of GoI and 260 airworthiness certification documents.