Polycrystalline Diamond Compact With Lower Interface Residual Stress
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional polycrystalline diamond compacts (PDCs) face premature failure due to residual stresses at the interface between the PCD table and the cemented carbide substrate, caused by differing coefficients of thermal expansion and modulus of elasticity, leading to de-bonding under thermal stresses and applied forces.
Innovation Solution
The development of PCDs with enhanced diamond-to-diamond bonding, achieved by sintering diamond particles at pressures of at least 7.5 GPa, resulting in a coercivity of 115 Oe or more and specific magnetic saturation of 15 G·cm3/g or less, with a metal-solvent catalyst content of 7.5 wt % or less, which promotes stronger interstitial bonding and reduced residual stresses.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional HPHT process is used to form PCD table bonded to cemented carbide substrate, then PDC can be manufactured, but residual stresses develop at the interface due to different coefficients of thermal expansion and modulus of elasticity, leading to premature failure
Solution Approach 1:
The patent applies parameter changes by sintering diamond particles at ultra-high pressures of at least 7.5 GPa (significantly higher than conventional HPHT pressures), which fundamentally alters the bonding characteristics and reduces residual stresses at the PCD-substrate interface, thereby improving PDC durability
Solution Approach 2:
The patent creates a composite structure where diamond particles are sintered in the presence of a metal-solvent catalyst to form a PCD table with enhanced bonding to the cemented carbide substrate. The composite nature of the PCD table (diamond grains bound by catalyst) allows for better stress distribution and reduced interface failures
2Strength
If sintering pressure is increased to at least 7.5 GPa to enhance diamond-to-diamond bonding, then thermal stability and wear resistance improve, but manufacturing complexity and energy requirements increase
Solution Approach 1:
The patent changes the pressure parameter to at least 7.5 GPa and maintains metal-solvent catalyst content at 7.5 wt% or less, achieving enhanced diamond-to-diamond bonding and improved thermal stability while managing the complexity through controlled parameter specification
Solution Approach 2:
The patent applies local quality by controlling the metal-solvent catalyst content to be 7.5 wt% or less, creating a specific composition regime that enhances bonding strength without requiring proportionally higher complexity in the manufacturing process
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances the thermal stability and wear resistance of PDCs, reducing residual stresses and preventing de-bonding, thereby improving the durability and performance of PDCs in applications like rotary drill bits and bearing apparatuses.
Implementation Method 1
A number of such cartridges may be loaded into an HPHT press. The substrates and volume of diamond particles are then processed under HPHT conditions in the presence of a catalyst material that causes the diamond particles to bond to one another to form a matrix of bonded diamond grains
Implementation Method 2
The substrates and volume of diamond particles are then processed under HPHT conditions in the presence of a catalyst material that causes the diamond particles to bond to one another to form a matrix of bonded diamond grains defining a polycrystalline diamond table
Implementation Method 3
a constituent of the cemented carbide substrate, such as cobalt from a cobalt-cemented tungsten carbide substrate, liquefies and sweeps from a region adjacent to the volume of diamond particles into interstitial regions between the diamond particles during the HPHT process
Data Source
AI summary
In an embodiment, a method of fabricating a polycrystalline diamond compact is disclosed. The method includes sintering a plurality of diamond particles in the presence of a metal-solvent catalyst to form a polycrystalline diamond body; leaching the polycrystalline diamond body to at least partially remove the metal-solvent catalyst therefrom, thereby forming an at least partially leached polycrystalline diamond body; and subjecting an assembly of the at least partially leached polycrystalline diamond body and a cemented carbide substrate to a high-pressure/high-temperature process at a pressure to infiltrate the at least partially leached polycrystalline diamond body with an infiltrant. The pressure of the high-pressure/high-temperature process is less than that employed in the act of sintering of the plurality of diamond particles.