# Alloy713LC vs IN738: A Comparative Analysis of High-Temperature Performance
## Introduction
In the realm of high-temperature applications, nickel-based superalloys play a crucial role in industries such as aerospace, power generation, and gas turbines. Among these, Alloy713LC and IN738 stand out as two prominent materials designed to withstand extreme conditions. This article provides a comprehensive comparison of these alloys, focusing on their composition, mechanical properties, and performance in high-temperature environments.
## Composition and Microstructure
Alloy713LC Composition
Alloy713LC is a low-carbon variant of the standard Alloy713, specifically designed to improve weldability while maintaining high-temperature strength. Its composition typically includes:
- Nickel (Ni): ~75%
- Chromium (Cr): ~12%
- Molybdenum (Mo): ~4.5%
- Aluminum (Al): ~6%
- Titanium (Ti): ~0.8%
- Carbon (C): ≤0.05% (low carbon content)
Keyword: Alloy713LC IN738
IN738 Composition
IN738 is another nickel-based superalloy with a more complex composition that enhances its high-temperature capabilities:
- Nickel (Ni): ~60%
- Chromium (Cr): ~16%
- Cobalt (Co): ~8.5%
- Molybdenum (Mo): ~1.7%
- Tungsten (W): ~2.6%
- Aluminum (Al): ~3.4%
- Titanium (Ti): ~3.4%
- Carbon (C): ~0.17%
## Mechanical Properties Comparison
Tensile Strength
At room temperature, both alloys demonstrate impressive tensile strength:
- Alloy713LC: ~1100 MPa
- IN738: ~1200 MPa
However, at elevated temperatures (around 800°C), IN738 maintains better strength retention due to its more complex precipitation hardening system.
Creep Resistance
Creep resistance is critical for high-temperature applications:
- Alloy713LC shows good creep resistance up to about 850°C
- IN738 demonstrates superior creep resistance, maintaining structural integrity up to 950°C
Thermal Fatigue Resistance
Thermal cycling performance:
- Alloy713LC has better thermal fatigue resistance in moderate temperature ranges
- IN738 performs better under extreme thermal cycling conditions
## High-Temperature Performance
Oxidation Resistance
Both alloys form protective oxide layers, but with different characteristics:
- Alloy713LC forms a primarily Cr₂O₃ layer
- IN738 develops a more complex Al₂O₃-based layer with better long-term stability
Hot Corrosion Resistance
In environments with sulfur and other corrosive elements:
- Alloy713LC shows moderate resistance to hot corrosion
- IN738, with its higher chromium content, demonstrates superior hot
