Похоже, вы можете использовать headerStyle prop для установки ширины.
import React from "react";
import MaterialTable from "material-table";
import ReactDOM from "react-dom";
import "./styles.css";
function App() {
return (
<MaterialTable
columns={[
{ title: "Name", field: "name", headerStyle: {width: "100px"} },
{ title: "Surname", field: "surname", headerStyle: {width: "100px"} },
{ title: "Birth Year", field: "birthYear", type: "numeric" },
]}
data={[
{ name: "Mehmet", surname: "Baran", birthYear: 1987, birthCity: 63 },
{
name: "Zerya Betül",
surname: "Baran",
birthYear: 2017,
birthCity: 34
}
]}
title="Basic"
options={{
toolbar: false,
paging: false
}}
/>
);
}
const rootElement = document.getElementById("root");
ReactDOM.render(<App />, rootElement);