Which is better, manganese copper alloy resistor or constantan alloy resistor?

Manganese copper alloy resistors and constantan alloy resistors each have their own characteristics in terms of stability. The following is a detailed analysis of their stability:
Stability of Manganese Copper Alloy Resistance

Temperature coefficient of resistance: Manganese copper alloy resistors have a very small temperature coefficient of resistance, which means that their resistance values change very little with temperature. Therefore, in environments with significant temperature changes, manganese copper alloy resistors can maintain relatively stable resistance values.
Resistance annual stability: Manganese copper alloy resistors also exhibit particularly excellent resistance annual stability, that is, their resistance values can remain stable and not easily change during long-term use.
Application scenarios: Due to these excellent stability characteristics, manganese copper alloy resistors are widely used in applications that require high precision and stability, such as metrology technology for electrical instruments and the production of standard resistors.

Stability of Copper Alloy Resistors

Temperature coefficient of resistance: Although the temperature coefficient of resistance of constantan alloy resistors is lower than that of general metals, it is still slightly higher compared to manganese copper alloy resistors. This means that the resistance value of the copper alloy resistor may have relatively large fluctuations when the temperature changes.
Corrosion resistance and oxidation resistance: Copper alloy resistors have good corrosion resistance and oxidation resistance due to the presence of chromium element. These characteristics help maintain the long-term stability of resistors, especially under harsh environmental conditions.
Application scenarios: Copper alloy resistors are widely used in the electronics, electrical, and heat treatment industries due to their stable resistivity and wide operating temperature range, such as making resistance elements, electric heating elements, etc.

summary
From a stability perspective, manganese copper alloy resistors perform better in terms of resistance temperature coefficient and resistance annual stability, making them particularly suitable for applications that require high precision and long-term stability. Although the stability of constantan alloy resistors is slightly inferior to that of manganese copper alloy resistors, they have strong corrosion resistance and oxidation resistance, making them suitable for use in harsh environmental conditions. When choosing, one should weigh the advantages and disadvantages of both based on specific application scenarios and requirements.