Few public artworks in Melbourne have generated as much controversy as Ron Robertson-Swann’s Vault.

Known colloquially as “Yellow Peril”, the infamous bright-yellow sculpture, made up of steel geometric pieces welded together, has remained a popular talking point.

Vault was chosen in 1978 by the city council for Melbourne’s then-new City Square. But at its debut in 1980, the work divided public opinion and attracted a number of derogative titles including, “The Thing” and “Steelhenge”.

Now part of a new National Gallery of Victoria Australia exhibition called Hard Edge, Robertson-Swann’s sculpture serves as a key work, emblematic of an important period in our history of sculpture.

“Ron’s work became something of a political football. It remains an interesting story and one that really sits deep in the culture of Melbourne.

“The idea of abstraction was something the general public did not immediately identify with,” says David Hurlston, NGV curator of Australian art. “People didn’t just dislike Vault, they became passionate in their dislike. Everyone seemed to have an opinion on it.”

Even the Queen expressed her distaste, suggesting it could have been painted “a more agreeable colour”.

The full-size sculpture is next to the Australian Centre for Contemporary Art in Southbank – it has been moved three times in its 40-year history. The original scale model is what is now on show at the NGV.

Hard Edge wants us to reflect on how we view Australian abstract sculpture. It collects together works by other prominent Australia sculptors, including Lenton Parr, Clive Murray-White and Inge King.

Set across two foyers at the NGV Federation Square, the exhibition emphasises the architectural beauty of these abstract sculptures, showing how they were a dramatic shift away from traditional forms of sculpture, and used steel instead of the usual wood, stone or bronze.

“The approach of these artists was to work with architects and designers and to think about the built environment incorporating sculpture,” says Hurlston.

Hard Edge also features Elwyn Dennis’ 1971 red-lacquered sculpture Evidence of Origin, a work that has sat inside the NGV for a number of years. Unlike Robertson-Swann’s Vault, Dennis’ work embraces soft smooth curves to suggest movement and motion.

Reflecting on Vault, Robertson-Swann himself says, “I didn’t intend to shock or provoke. If you look back, there were other artists who were way out there and avant-garde. But all that really shows is the gap between the art world and the public.

“Sculpture was the easy thing to target: public, bright yellow, unmistakable, right there in the city square.”

Hard Edge proves to be a provocative and thought-provoking exhibition, one that probes the meaning of sculptures and looks back at an important but sometimes overlooked period in Melbourne’s own public art history.

Hard Edge is now showing at National Gallery of Victoria at Federation Square and runs until July.

ngv.vic.gov.au/exhibition/hard-edge