# TMT Bars and Fe 500D Grade

> TMT bars are quenched steel reinforcement with a hard surface and ductile core. See what Fe 500D means and how SuperWise tracks steel deliveries and rates.

Canonical: https://superwise.site/glossary/tmt-bars/
Last updated: 2026-11-01

Water-quenched steel reinforcement bars with a hard outer surface and a ductile core, standard in Indian concrete work.

## What is TMT Bars (Thermo Mechanically Treated)?

TMT bars (thermo mechanically treated bars) have replaced older mild steel and cold-twisted bars in Indian civil engineering. They are made by passing hot steel through rapid water cooling, called quenching. The outer surface turns hard and strong, giving high tensile strength, while the inner core stays soft and ductile, so the bar can bend without snapping in an earthquake.

## Practical example

A structural engineer designing a hospital in a high-seismic zone specifies Fe 500D TMT bars for all columns. Fe 500 means a [yield strength](https://superwise.site/glossary/yield-strength/) of 500 MPa, and the D stands for ductility. In an earthquake these ductile bars stretch and absorb the shock energy, which keeps the columns from shattering.

## In SuperWise

TMT bars are a material resource in SuperWise, with a unit such as MT or kgs, a schedule of rates (SOR) and a minimum stock level. Steel is bought through an RFQ, where the [quotation](https://superwise.site/glossary/quotation/) comparison shows each vendor's rate, and the PO takes the discounted rate. Each delivery is recorded as a [material delivery challan](https://superwise.site/glossary/material-delivery-challan/) with a quality status.

[Material management](https://superwise.site/features/material-management/)

## Related terms

- [Yield Strength (Steel Rebar)](https://superwise.site/glossary/yield-strength/)
- [Bar Bending Schedule (BBS)](https://superwise.site/glossary/bar-bending-schedule/)
- [Reinforcement (Rebar)](https://superwise.site/glossary/reinforcement-rebar/)
- [Material Delivery Challan (MDC / GRN)](https://superwise.site/glossary/material-delivery-challan/)

## Related
- [Yield Strength (Steel Rebar)](https://superwise.site/glossary/yield-strength/)
- [Bar Bending Schedule (BBS)](https://superwise.site/glossary/bar-bending-schedule/)
- [Reinforcement (Rebar)](https://superwise.site/glossary/reinforcement-rebar/)
- [Material Delivery Challan (MDC / GRN)](https://superwise.site/glossary/material-delivery-challan/)
- [Material management](https://superwise.site/features/material-management/)