Brazing & High-Vacuum Metallurgy

Vacuum Induction Brazing Joint Gap Calculator

Model hot brazing clearance gaps ($h_{\text{hot}}$), thermal expansion differentials ($\Delta \alpha$), capillary flow rise ($H_{\text{cap}}$), filler alloy foil/wire volume, and joint shear strength for aerospace, nuclear, and rocket combustion chambers.

1. Input Parameters

Braze Filler Metal Alloy:

Standard AWS A5.8 vacuum braze filler alloy.

Nominal Joint Tube/Pin Diameter (D in mm):

Outside diameter of inner sleeve or mating male component.

Joint Overlap / Insertion Length (L in mm):

Axial overlap contact length between male and female parts.

Cold Room-Temperature Clearance Gap (h_0 in mm):

Radial clearance between parts at 20°C ambient room assembly.

Furnace Brazing Temperature (T_braze in °C):

Peak vacuum furnace dwell temperature.

Differential Thermal Expansion Δα (Outer - Inner in 10⁻⁶/K):

Thermal expansion coefficient mismatch between female socket and male plug.

2. Calculation Results

Hot Brazing Joint Gap (h_hot)

0.068 mm

Required Braze Alloy Volume

122.5 mm³

Capillary Rise Height (H_cap)

28.4 mm

Joint Ultimate Shear Capacity

41.8 kN

3. Geometric Visualizer

Tooling & Vector Prepress Engineering Notes

Vacuum Induction Brazing & Capillary Physics: Vacuum furnace brazing joins high-temperature alloys (Inconel, titanium, stainless steel) without corrosive flux. Molten filler alloy flows into micro-gaps driven by surface tension capillary wetting:

h_hot = h_0 + (D / 2) × (α_outer - α_inner) × (T_braze - 20°C) [mm]
Capillary Rise H_cap = (2 × γ × cos θ) / (ρ × g × h_hot) [mm]
Alloy Volume V = π × D × L × h_hot × (1 + Meniscus Fillet Factor ~ 1.25) [mm³]

Vector Prepress for Preforms & Stop-Off: Laser-cut foil preforms or wire rings must match the exact radial joint perimeter ($C = \pi \cdot D$). For selective brazing, program dispenser vector paths for Yttria/Alumina stop-off lacquer to prevent braze alloy wetting onto threads and precision sliding bores.